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Common Weakness Enumeration

CWE-203

Allowed

Observable Discrepancy

Abstraction: Base · Status: Incomplete

API response cwe.mitre.org

The product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor.

886 vulnerabilities reference this CWE, most recent first.

GHSA-FX2C-JQXX-QWCV

Vulnerability from github – Published: 2026-07-01 00:34 – Updated: 2026-07-01 18:31
VLAI
Details

Side-channel information leakage in CSS in Google Chrome prior to 150.0.7871.47 allowed a remote attacker to leak cross-origin data via a crafted HTML page. (Chromium security severity: Low)

Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
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{
  "affected": [],
  "aliases": [
    "CVE-2026-14085"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1300",
      "CWE-203"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-06-30T23:17:20Z",
    "severity": "MODERATE"
  },
  "details": "Side-channel information leakage in CSS in Google Chrome prior to 150.0.7871.47 allowed a remote attacker to leak cross-origin data via a crafted HTML page. (Chromium security severity: Low)",
  "id": "GHSA-fx2c-jqxx-qwcv",
  "modified": "2026-07-01T18:31:38Z",
  "published": "2026-07-01T00:34:10Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-14085"
    },
    {
      "type": "WEB",
      "url": "https://chromereleases.googleblog.com/2026/06/stable-channel-update-for-desktop_0175352312.html"
    },
    {
      "type": "WEB",
      "url": "https://issues.chromium.org/issues/513155863"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-G245-8P5F-GJMM

Vulnerability from github – Published: 2023-10-30 18:30 – Updated: 2023-11-06 18:30
VLAI
Details

In Slice, there is a possible disclosure of installed applications due to side channel information disclosure. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.

Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
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{
  "affected": [],
  "aliases": [
    "CVE-2023-21298"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-203"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2023-10-30T17:15:47Z",
    "severity": "HIGH"
  },
  "details": "In Slice, there is a possible disclosure of installed applications due to side channel information disclosure. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.",
  "id": "GHSA-g245-8p5f-gjmm",
  "modified": "2023-11-06T18:30:17Z",
  "published": "2023-10-30T18:30:24Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-21298"
    },
    {
      "type": "WEB",
      "url": "https://source.android.com/docs/security/bulletin/android-14"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-G2HF-9HJX-2RXJ

Vulnerability from github – Published: 2024-03-19 12:30 – Updated: 2025-11-04 21:31
VLAI
Details

NSS was susceptible to a timing side-channel attack when performing RSA decryption. This attack could potentially allow an attacker to recover the private data. This vulnerability affects Firefox < 124, Firefox ESR < 115.9, and Thunderbird < 115.9.

Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L
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{
  "affected": [],
  "aliases": [
    "CVE-2023-5388"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-203"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-03-19T12:15:07Z",
    "severity": "MODERATE"
  },
  "details": "NSS was susceptible to a timing side-channel attack when performing RSA decryption. This attack could potentially allow an attacker to recover the private data. This vulnerability affects Firefox \u003c 124, Firefox ESR \u003c 115.9, and Thunderbird \u003c 115.9.",
  "id": "GHSA-g2hf-9hjx-2rxj",
  "modified": "2025-11-04T21:31:20Z",
  "published": "2024-03-19T12:30:41Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-5388"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1780432"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2024/03/msg00010.html"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2024/03/msg00022.html"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2024/03/msg00028.html"
    },
    {
      "type": "WEB",
      "url": "https://www.mozilla.org/security/advisories/mfsa2024-12"
    },
    {
      "type": "WEB",
      "url": "https://www.mozilla.org/security/advisories/mfsa2024-13"
    },
    {
      "type": "WEB",
      "url": "https://www.mozilla.org/security/advisories/mfsa2024-14"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-G39F-Q9CX-H4C7

Vulnerability from github – Published: 2024-02-08 18:30 – Updated: 2024-02-15 06:31
VLAI
Details

php-jwt 1.0.0 uses strcmp (which is not constant time) to verify authentication, which makes it easier to bypass authentication via a timing side channel.

Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
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{
  "affected": [],
  "aliases": [
    "CVE-2024-25191"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-203"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-02-08T17:15:11Z",
    "severity": "CRITICAL"
  },
  "details": "php-jwt 1.0.0 uses strcmp (which is not constant time) to verify authentication, which makes it easier to bypass authentication via a timing side channel.",
  "id": "GHSA-g39f-q9cx-h4c7",
  "modified": "2024-02-15T06:31:34Z",
  "published": "2024-02-08T18:30:39Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-25191"
    },
    {
      "type": "WEB",
      "url": "https://github.com/P3ngu1nW/CVE_Request/blob/main/cdoco%3Aphp-jwt.md"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-G4CR-7M3R-2VRR

Vulnerability from github – Published: 2026-05-10 09:31 – Updated: 2026-05-11 15:32
VLAI
Details

A vulnerability was found in Industrial Application Software IAS Canias ERP 8.03. The impacted element is the function doAction of the component Login RMI Interface. Performing a manipulation results in observable response discrepancy. The attack is possible to be carried out remotely. A high degree of complexity is needed for the attack. The exploitability is regarded as difficult. The exploit has been made public and could be used. The vendor was contacted early about this disclosure but did not respond in any way.

Severity
3.7 (Low)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
2.9 (Low)
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P
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{
  "affected": [],
  "aliases": [
    "CVE-2026-8242"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-203"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-10T09:16:32Z",
    "severity": "LOW"
  },
  "details": "A vulnerability was found in Industrial Application Software IAS Canias ERP 8.03. The impacted element is the function doAction of the component Login RMI Interface. Performing a manipulation results in observable response discrepancy. The attack is possible to be carried out remotely. A high degree of complexity is needed for the attack. The exploitability is regarded as difficult. The exploit has been made public and could be used. The vendor was contacted early about this disclosure but did not respond in any way.",
  "id": "GHSA-g4cr-7m3r-2vrr",
  "modified": "2026-05-11T15:32:10Z",
  "published": "2026-05-10T09:31:33Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-8242"
    },
    {
      "type": "WEB",
      "url": "https://gist.github.com/0xb1lal/85422a63c10a001c75a22365457de624"
    },
    {
      "type": "WEB",
      "url": "https://hawktrace.com/blog/caniaserp"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/submit/808295"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/vuln/362458"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/vuln/362458/cti"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

GHSA-G4VP-4GQR-7V8C

Vulnerability from github – Published: 2025-08-19 21:30 – Updated: 2025-08-20 19:06
VLAI
Summary
Liferay Portal Enumeration Discrepancy in Calendars
Details

Liferay Portal 7.4.0 through 7.4.3.132, and Liferay DXP 2025.Q1.0 through 2025.Q1.5, 2024.Q4.0 through 2024.Q4.7, 2024.Q3.1 through 2024.Q3.13, 2024.Q2.0 through 2024.Q2.13, 2024.Q1.1 through 2024.Q1.15 and 7.4 GA through update 92 allows any authenticated remote user to view other calendars by allowing them to enumerate the names of other users, given an attacker the possibility to send phishing to these users.

Severity
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N
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{
  "affected": [
    {
      "package": {
        "ecosystem": "Maven",
        "name": "com.liferay.portal:release.portal.bom"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "7.4.0-ga1"
            },
            {
              "last_affected": "7.4.3.132-ga132"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-43743"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-203"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2025-08-20T19:06:54Z",
    "nvd_published_at": "2025-08-19T20:15:31Z",
    "severity": "MODERATE"
  },
  "details": "Liferay Portal 7.4.0 through 7.4.3.132, and Liferay DXP 2025.Q1.0 through 2025.Q1.5, 2024.Q4.0 through 2024.Q4.7, 2024.Q3.1 through 2024.Q3.13, 2024.Q2.0 through 2024.Q2.13, 2024.Q1.1 through 2024.Q1.15 and 7.4 GA through update 92 allows any authenticated remote user to view other calendars by allowing them to enumerate the names of other users, given an attacker the possibility to send phishing to these users.",
  "id": "GHSA-g4vp-4gqr-7v8c",
  "modified": "2025-08-20T19:06:54Z",
  "published": "2025-08-19T21:30:37Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-43743"
    },
    {
      "type": "WEB",
      "url": "https://github.com/liferay/liferay-portal/commit/02528147664475cd9f7205cd8bc05dfd43832201"
    },
    {
      "type": "WEB",
      "url": "https://github.com/liferay/liferay-portal/commit/144e4a276e456c4b7a0831ff038241f82a9181db"
    },
    {
      "type": "WEB",
      "url": "https://github.com/liferay/liferay-portal/commit/1513ed29f830c9119ee6be623ae783e545da4845"
    },
    {
      "type": "WEB",
      "url": "https://github.com/liferay/liferay-portal/commit/1e368205c710403e76749e38127419780acdda9d"
    },
    {
      "type": "WEB",
      "url": "https://github.com/liferay/liferay-portal/commit/7d6e1bccb62a41e944e0459d2c4b1eb9fdb31b8e"
    },
    {
      "type": "WEB",
      "url": "https://github.com/liferay/liferay-portal/commit/9a88f7fa98f9fc11a9eab444a256204cccc82b77"
    },
    {
      "type": "WEB",
      "url": "https://github.com/liferay/liferay-portal/commit/9aba859a6956786bcd8ce434ef063eed01b5ec6e"
    },
    {
      "type": "WEB",
      "url": "https://github.com/liferay/liferay-portal/commit/bd89933cc9022a98fc34b562ce3573a58f14cf38"
    },
    {
      "type": "WEB",
      "url": "https://github.com/liferay/liferay-portal/commit/d999a8e1902e88fdd7a26758f137925d969a639d"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/liferay/liferay-portal"
    },
    {
      "type": "WEB",
      "url": "https://liferay.atlassian.net/browse/LPE-18206"
    },
    {
      "type": "WEB",
      "url": "https://liferay.dev/portal/security/known-vulnerabilities/-/asset_publisher/jekt/content/CVE-2025-43743"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Liferay Portal Enumeration Discrepancy in Calendars"
}

GHSA-G56C-H972-7RHP

Vulnerability from github – Published: 2022-05-13 01:08 – Updated: 2022-05-13 01:08
VLAI
Details

Symantec SSL Visibility (SSLV) 3.8.4FC, 3.10 prior to 3.10.4.1, 3.11, and 3.12 prior to 3.12.2.1 are vulnerable to the Return of the Bleichenbacher Oracle Threat (ROBOT) attack. All affected SSLV versions act as weak oracles according the oracle classification used in the ROBOT research paper. A remote attacker, who has captured a pre-recorded SSL session inspected by SSLV, can establish multiple millions of crafted SSL connections to the target and obtain the session keys required to decrypt the pre-recorded SSL session.

Severity
5.9 (Medium)
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Show details on source website
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{
  "affected": [],
  "aliases": [
    "CVE-2017-15533"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-203"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2018-05-17T13:29:00Z",
    "severity": "MODERATE"
  },
  "details": "Symantec SSL Visibility (SSLV) 3.8.4FC, 3.10 prior to 3.10.4.1, 3.11, and 3.12 prior to 3.12.2.1 are vulnerable to the Return of the Bleichenbacher Oracle Threat (ROBOT) attack. All affected SSLV versions act as weak oracles according the oracle classification used in the ROBOT research paper. A remote attacker, who has captured a pre-recorded SSL session inspected by SSLV, can establish multiple millions of crafted SSL connections to the target and obtain the session keys required to decrypt the pre-recorded SSL session.",
  "id": "GHSA-g56c-h972-7rhp",
  "modified": "2022-05-13T01:08:58Z",
  "published": "2022-05-13T01:08:58Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2017-15533"
    },
    {
      "type": "WEB",
      "url": "https://www.symantec.com/security-center/network-protection-security-advisories/SA160"
    },
    {
      "type": "WEB",
      "url": "http://www.securityfocus.com/bid/104163"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-G58R-FCX4-MV8R

Vulnerability from github – Published: 2025-01-14 15:30 – Updated: 2025-01-14 15:30
VLAI
Details

An observable response discrepancy vulnerability [CWE-204] in FortiClientEMS 7.4.0, 7.2.0 through 7.2.4, 7.0 all versions, and FortiSOAR 7.5.0, 7.4.0 through 7.4.4, 7.3.0 through 7.3.2, 7.2 all versions, 7.0 all versions, 6.4 all versions may allow an unauthenticated attacker to enumerate valid users via observing login request responses.

Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Show details on source website
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{
  "affected": [],
  "aliases": [
    "CVE-2024-36510"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-203",
      "CWE-204"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-01-14T14:15:30Z",
    "severity": "MODERATE"
  },
  "details": "An observable response discrepancy vulnerability [CWE-204] in FortiClientEMS 7.4.0, 7.2.0 through 7.2.4, 7.0 all versions, and FortiSOAR 7.5.0, 7.4.0 through 7.4.4, 7.3.0 through 7.3.2, 7.2 all versions, 7.0 all versions, 6.4 all versions may allow an unauthenticated attacker to enumerate valid users via observing login request responses.",
  "id": "GHSA-g58r-fcx4-mv8r",
  "modified": "2025-01-14T15:30:53Z",
  "published": "2025-01-14T15:30:53Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-36510"
    },
    {
      "type": "WEB",
      "url": "https://fortiguard.fortinet.com/psirt/FG-IR-24-071"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-G5VH-55HW-RXM8

Vulnerability from github – Published: 2026-07-02 13:46 – Updated: 2026-07-02 13:46
VLAI
Summary
GoFiber Vulnerable to Username Enumeration via Timing Oracle in BasicAuth Default Authorizer
Details

Summary

The default Authorizer function in GoFiber's BasicAuth middleware uses short-circuit evaluation that skips password hash comparison for non-existent usernames. With bcrypt-hashed passwords (the primary use case), the timing difference between a valid and invalid username is approximately 1,000,000:1 (~100ms vs ~100ns), enabling reliable remote username enumeration.

Vulnerable Code

File: middleware/basicauth/config.go, lines 126-138

if cfg.Authorizer == nil {
    verifiers := make(map[string]func(string) bool, len(cfg.Users))
    for u, hpw := range cfg.Users {
        v, err := parseHashedPassword(hpw)
        if err != nil {
            panic(err)
        }
        verifiers[u] = v
    }
    cfg.Authorizer = func(user, pass string, _ fiber.Ctx) bool {
        verify, ok := verifiers[user]
        return ok && verify(pass)   // line 137: short-circuit skips verify() if user unknown
    }
}

Data Flow

  1. Attacker sends Authorization: Basic <base64(candidate:wrongpass)>
  2. BasicAuth middleware decodes credentials and calls cfg.Authorizer(user, pass, c)
  3. Map lookup verifiers[user] returns ok=false for non-existent users
  4. Go && short-circuit: false && verify(pass) returns immediately without calling verify()
  5. For valid users, verify(pass) executes bcrypt.CompareHashAndPassword() (line 167: ~100ms at default cost 10)
  6. Timing difference: ~100ns (invalid user) vs ~100ms (valid user) = 1,000,000:1 ratio

Timing comparison by hash type:

Hash Type Valid User Invalid User Ratio
bcrypt ($2) ~100 ms ~100 ns 1,000,000:1
SHA-512 ~1-5 us ~100 ns 10-50:1
SHA-256 ~1-5 us ~100 ns 10-50:1

Impact

  • Username enumeration: Attacker reliably determines which usernames exist by measuring response latency
  • Targeted brute force: After enumerating valid usernames, password brute force is focused only on real accounts
  • Account discovery: In applications where usernames are sensitive (internal tools, admin panels), leaking their existence is itself a security issue

Notes

  • Password hash comparisons themselves are timing-safe: subtle.ConstantTimeCompare is used correctly for SHA-256 (line 185), SHA-512 (line 176), and bcrypt uses its own constant-time comparison
  • The fix is to always execute a dummy hash comparison for unknown users: bcrypt.CompareHashAndPassword(dummyHash, []byte(pass)) and discard the result
  • This pattern matches CVE-2023-36456 (Authentik timing oracle) and similar findings in other auth libraries
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Show details on source website
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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 3.2.0"
      },
      "package": {
        "ecosystem": "Go",
        "name": "github.com/gofiber/fiber/v3"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.3.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-44332"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-203"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-07-02T13:46:25Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "## Summary\n\nThe default `Authorizer` function in GoFiber\u0027s BasicAuth middleware uses short-circuit evaluation that skips password hash comparison for non-existent usernames. With bcrypt-hashed passwords (the primary use case), the timing difference between a valid and invalid username is approximately 1,000,000:1 (~100ms vs ~100ns), enabling reliable remote username enumeration.\n\n## Vulnerable Code\n\n**File:** `middleware/basicauth/config.go`, lines 126-138\n\n```go\nif cfg.Authorizer == nil {\n    verifiers := make(map[string]func(string) bool, len(cfg.Users))\n    for u, hpw := range cfg.Users {\n        v, err := parseHashedPassword(hpw)\n        if err != nil {\n            panic(err)\n        }\n        verifiers[u] = v\n    }\n    cfg.Authorizer = func(user, pass string, _ fiber.Ctx) bool {\n        verify, ok := verifiers[user]\n        return ok \u0026\u0026 verify(pass)   // line 137: short-circuit skips verify() if user unknown\n    }\n}\n```\n\n## Data Flow\n\n1. Attacker sends `Authorization: Basic \u003cbase64(candidate:wrongpass)\u003e`\n2. BasicAuth middleware decodes credentials and calls `cfg.Authorizer(user, pass, c)`\n3. Map lookup `verifiers[user]` returns `ok=false` for non-existent users\n4. Go `\u0026\u0026` short-circuit: `false \u0026\u0026 verify(pass)` returns immediately without calling `verify()`\n5. For valid users, `verify(pass)` executes `bcrypt.CompareHashAndPassword()` (line 167: ~100ms at default cost 10)\n6. Timing difference: ~100ns (invalid user) vs ~100ms (valid user) = 1,000,000:1 ratio\n\n**Timing comparison by hash type:**\n\n| Hash Type | Valid User | Invalid User | Ratio |\n|-----------|-----------|--------------|-------|\n| bcrypt ($2) | ~100 ms | ~100 ns | 1,000,000:1 |\n| SHA-512 | ~1-5 us | ~100 ns | 10-50:1 |\n| SHA-256 | ~1-5 us | ~100 ns | 10-50:1 |\n\n## Impact\n\n- **Username enumeration:** Attacker reliably determines which usernames exist by measuring response latency\n- **Targeted brute force:** After enumerating valid usernames, password brute force is focused only on real accounts\n- **Account discovery:** In applications where usernames are sensitive (internal tools, admin panels), leaking their existence is itself a security issue\n\n## Notes\n\n- Password hash comparisons themselves are timing-safe: `subtle.ConstantTimeCompare` is used correctly for SHA-256 (line 185), SHA-512 (line 176), and bcrypt uses its own constant-time comparison\n- The fix is to always execute a dummy hash comparison for unknown users: `bcrypt.CompareHashAndPassword(dummyHash, []byte(pass))` and discard the result\n- This pattern matches CVE-2023-36456 (Authentik timing oracle) and similar findings in other auth libraries",
  "id": "GHSA-g5vh-55hw-rxm8",
  "modified": "2026-07-02T13:46:25Z",
  "published": "2026-07-02T13:46:25Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/gofiber/fiber/security/advisories/GHSA-g5vh-55hw-rxm8"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/gofiber/fiber"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "GoFiber Vulnerable to Username Enumeration via Timing Oracle in BasicAuth Default Authorizer"
}

GHSA-G62R-H4Q8-QX29

Vulnerability from github – Published: 2022-05-24 19:02 – Updated: 2022-05-24 19:02
VLAI
Details

Nordic Semiconductor nRF52840 devices through 2020-10-19 have improper protection against physical side channels. The flash read-out protection (APPROTECT) can be bypassed by injecting a fault during the boot phase.

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

{
  "affected": [],
  "aliases": [
    "CVE-2020-27211"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-203",
      "CWE-74"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2021-05-21T13:15:00Z",
    "severity": "MODERATE"
  },
  "details": "Nordic Semiconductor nRF52840 devices through 2020-10-19 have improper protection against physical side channels. The flash read-out protection (APPROTECT) can be bypassed by injecting a fault during the boot phase.",
  "id": "GHSA-g62r-h4q8-qx29",
  "modified": "2022-05-24T19:02:57Z",
  "published": "2022-05-24T19:02:57Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-27211"
    },
    {
      "type": "WEB",
      "url": "https://eprint.iacr.org/2021/640"
    },
    {
      "type": "WEB",
      "url": "https://infocenter.nordicsemi.com/pdf/in_133_v1.0.pdf"
    },
    {
      "type": "WEB",
      "url": "https://limitedresults.com/2020/06/nrf52-debug-resurrection-approtect-bypass"
    },
    {
      "type": "WEB",
      "url": "https://www.aisec.fraunhofer.de/de/das-institut/wissenschaftliche-exzellenz/security-and-trust-in-open-source-security-tokens.html"
    },
    {
      "type": "WEB",
      "url": "https://www.aisec.fraunhofer.de/en/FirmwareProtection.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:P/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ]
}
Mitigation MIT-46
Architecture and Design

Strategy: Separation of Privilege

  • Compartmentalize the system to have "safe" areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area.
  • Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.
Mitigation MIT-39
Implementation
  • Ensure that error messages only contain minimal details that are useful to the intended audience and no one else. The messages need to strike the balance between being too cryptic (which can confuse users) or being too detailed (which may reveal more than intended). The messages should not reveal the methods that were used to determine the error. Attackers can use detailed information to refine or optimize their original attack, thereby increasing their chances of success.
  • If errors must be captured in some detail, record them in log messages, but consider what could occur if the log messages can be viewed by attackers. Highly sensitive information such as passwords should never be saved to log files.
  • Avoid inconsistent messaging that might accidentally tip off an attacker about internal state, such as whether a user account exists or not.
CAPEC-189: Black Box Reverse Engineering

An adversary discovers the structure, function, and composition of a type of computer software through black box analysis techniques. 'Black Box' methods involve interacting with the software indirectly, in the absence of direct access to the executable object. Such analysis typically involves interacting with the software at the boundaries of where the software interfaces with a larger execution environment, such as input-output vectors, libraries, or APIs. Black Box Reverse Engineering also refers to gathering physical side effects of a hardware device, such as electromagnetic radiation or sounds.

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