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OESA-2026-2404 (CVE-2026-3833)

Vulnerability from osv_openeuler – Published: 2026-05-22 11:11 – Updated: 2026-08-06 11:11 – Source website
VLAI
Summary
gnutls security update
Details

GnuTLS is a secure communications library implementing the SSL, TLS and DTLS protocols and technologies around them. It provides a simple C language application programming interface (API) to access the secure communications protocols as well as APIs to parse and write X.509, PKCS #12, and other required structures. The project strives to provide a secure communications back-end, simple to use and integrated with the rest of the base Linux libraries. A back-end designed to work and be secure out of the box, keeping the complexity of TLS and PKI out of application code.

Security Fix(es):

A flaw was found in gnutls. This vulnerability occurs because gnutls performs case-sensitive comparisons of nameConstraints labels, specifically for dNSName (DNS) or rfc822Name (email) constraints within excludedSubtrees or permittedSubtrees. A remote attacker can exploit this by crafting a leaf certificate with casing differences in the Subject Alternative Name (SAN), leading to a policy bypass where a certificate that should be rejected is instead accepted. This could result in unauthorized access or information disclosure.(CVE-2026-3833)

A flaw was found in gnutls. A remote attacker could exploit an issue in the Datagram Transport Layer Security (DTLS) packet reordering logic. The comparator function, responsible for ordering DTLS packets by sequence numbers, did not correctly handle packets with duplicate sequence numbers. This could lead to unstable packet ordering or undefined behavior, resulting in a denial of service.(CVE-2026-42009)

A flaw was found in gnutls. Servers configured with RSA-PSK (Rivest–Shamir–Adleman – Pre-Shared Key) wrongfully matched usernames containing a NUL character with truncated usernames. A remote attacker could exploit this by sending a specially crafted username, leading to an authentication bypass. This vulnerability allows an attacker to gain unauthorized access by circumventing the authentication process.(CVE-2026-42010)

(CVE-2026-42013)

(CVE-2026-42014)

(CVE-2026-42015)

(CVE-2026-5260)

Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "aarch64": [
          "gnutls-3.7.2-23.oe2203sp4.aarch64.rpm",
          "gnutls-debuginfo-3.7.2-23.oe2203sp4.aarch64.rpm",
          "gnutls-debugsource-3.7.2-23.oe2203sp4.aarch64.rpm",
          "gnutls-devel-3.7.2-23.oe2203sp4.aarch64.rpm",
          "gnutls-utils-3.7.2-23.oe2203sp4.aarch64.rpm"
        ],
        "noarch": [
          "gnutls-help-3.7.2-23.oe2203sp4.noarch.rpm"
        ],
        "src": [
          "gnutls-3.7.2-23.oe2203sp4.src.rpm"
        ],
        "x86_64": [
          "gnutls-3.7.2-23.oe2203sp4.x86_64.rpm",
          "gnutls-debuginfo-3.7.2-23.oe2203sp4.x86_64.rpm",
          "gnutls-debugsource-3.7.2-23.oe2203sp4.x86_64.rpm",
          "gnutls-devel-3.7.2-23.oe2203sp4.x86_64.rpm",
          "gnutls-utils-3.7.2-23.oe2203sp4.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:22.03-LTS-SP4",
        "name": "gnutls",
        "purl": "pkg:rpm/openEuler/gnutls\u0026distro=openEuler-22.03-LTS-SP4"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.7.2-23.oe2203sp4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "severity": "Critical"
  },
  "details": "GnuTLS is a secure communications library implementing the SSL, TLS and DTLS protocols and technologies around them. It provides a simple C language application programming interface (API) to access the secure communications protocols as well as APIs to parse and write X.509, PKCS #12, and other required structures. The project strives to provide a secure communications back-end, simple to use and integrated with the rest of the base Linux libraries. A back-end designed to work and be secure out of the box, keeping the complexity of TLS and PKI out of application code.\r\n\r\nSecurity Fix(es):\n\nA flaw was found in gnutls. This vulnerability occurs because gnutls performs case-sensitive comparisons of `nameConstraints` labels, specifically for `dNSName` (DNS) or `rfc822Name` (email) constraints within `excludedSubtrees` or `permittedSubtrees`. A remote attacker can exploit this by crafting a leaf certificate with casing differences in the Subject Alternative Name (SAN), leading to a policy bypass where a certificate that should be rejected is instead accepted. This could result in unauthorized access or information disclosure.(CVE-2026-3833)\n\nA flaw was found in gnutls. A remote attacker could exploit an issue in the Datagram Transport Layer Security (DTLS) packet reordering logic. The comparator function, responsible for ordering DTLS packets by sequence numbers, did not correctly handle packets with duplicate sequence numbers. This could lead to unstable packet ordering or undefined behavior, resulting in a denial of service.(CVE-2026-42009)\n\nA flaw was found in gnutls. Servers configured with RSA-PSK (Rivest\u2013Shamir\u2013Adleman \u2013 Pre-Shared Key) wrongfully matched usernames containing a NUL character with truncated usernames. A remote attacker could exploit this by sending a specially crafted username, leading to an authentication bypass. This vulnerability allows an attacker to gain unauthorized access by circumventing the authentication process.(CVE-2026-42010)\n\n(CVE-2026-42013)\n\n(CVE-2026-42014)\n\n(CVE-2026-42015)\n\n(CVE-2026-5260)",
  "id": "OESA-2026-2404",
  "modified": "2026-08-06T11:11:21Z",
  "published": "2026-05-22T11:11:21Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-2404"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-3833"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-42009"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-42010"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-42013"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-42014"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-42015"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-5260"
    }
  ],
  "schema_version": "1.7.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "gnutls security update",
  "upstream": [
    "CVE-2026-3833",
    "CVE-2026-42009",
    "CVE-2026-42010",
    "CVE-2026-42013",
    "CVE-2026-42014",
    "CVE-2026-42015",
    "CVE-2026-5260"
  ]
}



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