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GHSA-2X5J-VHC8-9CWM

Vulnerability from github – Published: 2025-06-10 21:18 – Updated: 2025-10-23 17:36
VLAI
Summary
CIRCL-Fourq: Missing and wrong validation can lead to incorrect results
Details

Impact

The CIRCL implementation of FourQ fails to validate user-supplied low-order points during Diffie-Hellman key exchange, potentially allowing attackers to force the identity point and compromise session security.

Moreover, there is an incorrect point validation in ScalarMult can lead to incorrect results in the isEqual function and if a point is on the curve.

Patches

Version 1.6.1 (https://github.com/cloudflare/circl/tree/v1.6.1) mitigates the identified issues.

We acknowledge Alon Livne (Botanica Software Labs) for the reported findings.

Severity
3.7 (Low)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
Show details on source website
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{
  "affected": [
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/cloudflare/circl"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.6.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-8556"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-20",
      "CWE-347"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2025-06-10T21:18:33Z",
    "nvd_published_at": null,
    "severity": "LOW"
  },
  "details": "### Impact\nThe CIRCL implementation of FourQ fails to validate user-supplied low-order points during Diffie-Hellman key exchange, potentially allowing attackers to force the identity point and compromise session security.\n\nMoreover, there is an incorrect point validation in ScalarMult can lead to incorrect results in the isEqual function and if a point is on the curve.\n\n\n### Patches\nVersion 1.6.1 (https://github.com/cloudflare/circl/tree/v1.6.1) mitigates the identified issues.\n\nWe acknowledge Alon Livne (Botanica Software Labs) for the reported findings.",
  "id": "GHSA-2x5j-vhc8-9cwm",
  "modified": "2025-10-23T17:36:51Z",
  "published": "2025-06-10T21:18:33Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/cloudflare/circl/security/advisories/GHSA-2x5j-vhc8-9cwm"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-8556"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2025-8556"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2371624"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/cloudflare/circl"
    },
    {
      "type": "WEB",
      "url": "https://github.com/cloudflare/circl/tree/v1.6.1"
    },
    {
      "type": "WEB",
      "url": "https://news.ycombinator.com/item?id=45669593"
    },
    {
      "type": "WEB",
      "url": "https://www.botanica.software/blog/cryptographic-issues-in-cloudflares-circl-fourq-implementation"
    }
  ],
  "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"
    }
  ],
  "summary": "CIRCL-Fourq: Missing and wrong validation can lead to incorrect results"
}



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