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GHSA-GRH8-3P95-F9RR

Vulnerability from github – Published: 2026-09-15 20:00 – Updated: 2026-09-15 20:00
VLAI
Summary
Http4s: CookieJar middleware matches by substring, leaking cookies cross-origin
Details

The CookieJar client middleware decides whether to attach a cookie to an outgoing request using an unanchored substring test on the host and path, instead of the domain match specified by RFC6265 5.1.3. A cookie stored for example.com is therefore sent to any host whose name merely contains example.com (e.g. evilexample.com), leaking potentially sensitive cookies to an attacker-chosen host.

Impact

Disclosure of session and authentication cookies to an attacker-controlled host, enabling session hijack of the application's outbound calls.

Preconditions

  • Application uses the CookieJar client middleware.
  • Application can be induced to make an outbound request to a host controlled by the attacker, where the hostname contains the targeted domain as a substring.

Workarounds

  • Do not use the CookieJar with clients that fetch attacker-influenced URLs
  • Apply a separate CookieJar per trusted origin.
Severity
6.8 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N
Show details on source website
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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 0.23.34"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.http4s:http4s-client_2.12"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.23.35"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 0.23.34"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.http4s:http4s-client_2.13"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.23.35"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 0.23.34"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.http4s:http4s-client_3"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.23.35"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 1.0.0-M46"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.http4s:http4s-client_2.13"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "1.0.0-M1"
            },
            {
              "fixed": "1.0.0-M47"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 1.0.0-M46"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.http4s:http4s-client_3"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "1.0.0-M1"
            },
            {
              "fixed": "1.0.0-M47"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-69215"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1275",
      "CWE-565"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-09-15T20:00:54Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "The `CookieJar` client middleware decides whether to attach a cookie to an outgoing request using an unanchored substring test on the host and path, instead of the domain match specified by RFC6265 5.1.3.  A cookie stored for `example.com` is therefore sent to any host whose name merely contains `example.com` (e.g. `evilexample.com`), leaking potentially sensitive cookies to an attacker-chosen host.\n\n## Impact\n\nDisclosure of session and authentication cookies to an attacker-controlled host, enabling session hijack of the application\u0027s outbound calls.\n\n## Preconditions\n\n- Application uses the `CookieJar` client middleware.\n- Application can be induced to make an outbound request to a host controlled by the attacker, where the hostname contains the targeted domain as a substring.\n\n## Workarounds\n\n- Do not use the `CookieJar` with clients that fetch attacker-influenced URLs\n- Apply a separate `CookieJar` per trusted origin.",
  "id": "GHSA-grh8-3p95-f9rr",
  "modified": "2026-09-15T20:00:54Z",
  "published": "2026-09-15T20:00:54Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/http4s/http4s/security/advisories/GHSA-grh8-3p95-f9rr"
    },
    {
      "type": "WEB",
      "url": "https://github.com/http4s/http4s/commit/c0a37f38d5ee2a568ba57bd9da62f8d79b8b1fcc"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/http4s/http4s"
    },
    {
      "type": "WEB",
      "url": "https://github.com/http4s/http4s/releases/tag/v0.23.35"
    },
    {
      "type": "WEB",
      "url": "https://github.com/http4s/http4s/releases/tag/v1.0.0-M47"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Http4s: CookieJar middleware matches by substring, leaking cookies cross-origin"
}



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