Vulnerability-Lookup

GHSA-MH64-PH39-MRC9

Vulnerability from github – Published: 2026-06-19 22:10 – Updated: 2026-06-19 22:10

Summary

Cloudflare Quiche: Use-after-free in connection ID iterator FFI functions

Details

Impact

Cloudflare Quiche was affected by 2 use-after-free vulnerabilities in the connection ID iterator FFI functions.

The quiche_connection_id_iter_next and quiche_conn_retired_scid_next functions would return a pointer to a ConnectionId to the applications via function arguments, but the the owned ConnectionId would be dropped at the end of those functions' scope.

Only applications using those FFI functions are affected. The FFI API is disabled by default by a build-time feature flag.

quiche 0.29.2 is the earliest version containing the fix for this issue.

Severity

5.6 (Medium)


                  
                    CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "crates.io",
        "name": "quiche"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0.20.0"
            },
            {
              "fixed": "0.29.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-11941"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-416"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-19T22:10:29Z",
    "nvd_published_at": "2026-06-19T12:16:26Z",
    "severity": "MODERATE"
  },
  "details": "### Impact\n\nCloudflare Quiche was affected by 2 use-after-free vulnerabilities in the connection ID iterator FFI functions.\n\nThe `quiche_connection_id_iter_next` and `quiche_conn_retired_scid_next` functions would return a pointer to a `ConnectionId` to the applications via function arguments, but the the owned `ConnectionId` would be dropped at the end of those functions\u0027 scope.\n\nOnly applications using those FFI functions are affected. The FFI API is disabled by default by a build-time feature flag.\n\nquiche 0.29.2 is the earliest version containing the fix for this issue.",
  "id": "GHSA-mh64-ph39-mrc9",
  "modified": "2026-06-19T22:10:29Z",
  "published": "2026-06-19T22:10:29Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/cloudflare/quiche/security/advisories/GHSA-mh64-ph39-mrc9"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-11941"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/cloudflare/quiche"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Cloudflare Quiche: Use-after-free in connection ID iterator FFI functions"
}

CVE-2026-11941 (GCVE-0-2026-11941)

Vulnerability from cvelistv5 – Published: 2026-06-19 09:55 – Updated: 2026-06-22 15:10

Title

Use-after-free in connection ID iterator and FFI functions

Summary

Cloudflare Quiche was affected by 2 use-after-free vulnerabilities in the connection ID iterator FFI functions. The “quiche_connection_id_iter_next” and “quiche_conn_retired_scid_next” functions would return a pointer to a “ConnectionId” to the applications via function arguments, but the owned “ConnectionId” would be dropped at the end of those functions' scope. Only applications using those FFI functions are affected. The FFI API is disabled by default by a build-time feature flag. Impact If unpatched, an application calling the affected FFI functions will dereference freed memory. The most likely outcome is undefined behavior leading to a process crash (denial of service). Depending on allocator state, the read may also return adjacent heap contents, resulting in limited information disclosure or incorrect connection identifier handling. Mitigation Users are requested to upgrade to quiche 0.29.2 which is the earliest version containing the fix for this issue.

Severity

5.6 (Medium)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-22 15:09 UTC

CWE

CWE-416 - Use after free

Assigner

cloudflare mitre root

References

1 reference

URL	Tags
https://github.com/cloudflare/quiche/security/adv…

Impacted products

1 product

Vendor	Product	Version
Cloudflare	Quiche	Affected: 0.20.0 , ≤ 0.29.1 (semver)

Date Public

2026-06-19 09:49

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-11941",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-22T15:09:49.880714Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-22T15:10:00.033Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Quiche",
          "repo": "https://github.com/cloudflare/quiche",
          "vendor": "Cloudflare",
          "versions": [
            {
              "lessThanOrEqual": "0.29.1",
              "status": "affected",
              "version": "0.20.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "datePublic": "2026-06-19T09:49:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003cp\u003eCloudflare Quiche was affected by 2 use-after-free vulnerabilities in the connection ID iterator FFI functions.\u003c/p\u003e\u003cp\u003eThe \u201cquiche_connection_id_iter_next\u201d and \u201cquiche_conn_retired_scid_next\u201d functions would return a pointer to a \u201cConnectionId\u201d to the applications via function arguments, but the owned \u201cConnectionId\u201d would be dropped at the end of those functions\u0027 scope.\u003c/p\u003e\u003cp\u003eOnly applications using those FFI functions are affected. The FFI API is disabled by default by a build-time feature flag.\u003c/p\u003e\u003cp\u003e\u003cspan\u003e\u003cb\u003eImpact\u003cbr\u003e\u003c/b\u003e\u003c/span\u003e\u003cspan\u003eIf unpatched, an application calling the affected FFI functions will dereference freed memory. The most likely outcome is undefined behavior leading to a process crash (denial of service). Depending on allocator state, the read may also return adjacent heap contents, resulting in limited information disclosure or incorrect connection identifier handling.\u003c/span\u003e\u003c/p\u003e\u003cp\u003e\u003cspan\u003e\u003cb\u003eMitigation\u003cbr\u003e\u003c/b\u003e\u003c/span\u003e\u003cspan\u003eUsers are requested to upgrade to quiche 0.29.2 which is the earliest version containing the fix for this issue.\u003c/span\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003e\u003c/b\u003e\u003cbr\u003e\u003c/p\u003e\u003cbr\u003e"
            }
          ],
          "value": "Cloudflare Quiche was affected by 2 use-after-free vulnerabilities in the connection ID iterator FFI functions.\n\n\n\nThe \u201cquiche_connection_id_iter_next\u201d and \u201cquiche_conn_retired_scid_next\u201d functions would return a pointer to a \u201cConnectionId\u201d to the applications via function arguments, but the owned \u201cConnectionId\u201d would be dropped at the end of those functions\u0027 scope.\n\n\n\nOnly applications using those FFI functions are affected. The FFI API is disabled by default by a build-time feature flag.\n\n\n\nImpact\nIf unpatched, an application calling the affected FFI functions will dereference freed memory. The most likely outcome is undefined behavior leading to a process crash (denial of service). Depending on allocator state, the read may also return adjacent heap contents, resulting in limited information disclosure or incorrect connection identifier handling.\n\n\n\nMitigation\nUsers are requested to upgrade to quiche 0.29.2 which is the earliest version containing the fix for this issue."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "LOW",
            "baseScore": 5.6,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-416",
              "description": "CWE-416 Use after free",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-19T09:55:54.501Z",
        "orgId": "a22f1246-ba21-4bb4-a601-ad51614c1513",
        "shortName": "cloudflare"
      },
      "references": [
        {
          "url": "https://github.com/cloudflare/quiche/security/advisories/GHSA-mh64-ph39-mrc9"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "Use-after-free in connection ID iterator and FFI functions",
      "x_generator": {
        "engine": "Vulnogram 1.0.2"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a22f1246-ba21-4bb4-a601-ad51614c1513",
    "assignerShortName": "cloudflare",
    "cveId": "CVE-2026-11941",
    "datePublished": "2026-06-19T09:55:54.501Z",
    "dateReserved": "2026-06-10T20:16:34.590Z",
    "dateUpdated": "2026-06-22T15:10:00.033Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.