Vulnerability-Lookup

GHSA-V3J5-MP2X-9859

Vulnerability from github – Published: 2026-09-09 18:32 – Updated: 2026-09-10 06:31

Details

In the Linux kernel, the following vulnerability has been resolved:

crypto: krb5 - use kfree_sensitive() for derived key buffers

crypto_krb5_prepare_encryption() and crypto_krb5_prepare_checksum() free the buffer holding the freshly derived keys with plain kfree(), leaving the key material behind in the freed slab object.

Severity

7.5 (High)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-80924"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-09T17:17:47Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: krb5 - use kfree_sensitive() for derived key buffers\n\ncrypto_krb5_prepare_encryption() and crypto_krb5_prepare_checksum()\nfree the buffer holding the freshly derived keys with plain kfree(),\nleaving the key material behind in the freed slab object.",
  "id": "GHSA-v3j5-mp2x-9859",
  "modified": "2026-09-10T06:31:41Z",
  "published": "2026-09-09T18:32:04Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-80924"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/731a5b6fb4c1705f9405d9029dd64ea81e336207"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/91b96dc9cc250cd16751f53de525cf3442ca0962"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a1bf79365794783b19f5b09e8a23f7ee311e8931"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f7d53dd3f267e46a784f219a75072f2f400d42b9"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-80924 (GCVE-0-2026-80924)

Vulnerability from cvelistv5 – Published: 2026-09-09 16:19 – Updated: 2026-09-10 05:50

Title

crypto: krb5 - use kfree_sensitive() for derived key buffers

Summary

In the Linux kernel, the following vulnerability has been resolved: crypto: krb5 - use kfree_sensitive() for derived key buffers crypto_krb5_prepare_encryption() and crypto_krb5_prepare_checksum() free the buffer holding the freshly derived keys with plain kfree(), leaving the key material behind in the freed slab object.

Severity

7.5 (High)


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

Assigner

Linux mitre root

References

4 references

URL	Tags
https://git.kernel.org/stable/c/731a5b6fb4c1705f9…
https://git.kernel.org/stable/c/91b96dc9cc250cd16…
https://git.kernel.org/stable/c/a1bf79365794783b1…
https://git.kernel.org/stable/c/f7d53dd3f267e46a7…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 3936f02bf2d3308a7359dd37dd96cd60603d8170 , < 731a5b6fb4c1705f9405d9029dd64ea81e336207 (git) Affected: 3936f02bf2d3308a7359dd37dd96cd60603d8170 , < 91b96dc9cc250cd16751f53de525cf3442ca0962 (git) Affected: 3936f02bf2d3308a7359dd37dd96cd60603d8170 , < a1bf79365794783b19f5b09e8a23f7ee311e8931 (git) Affected: 3936f02bf2d3308a7359dd37dd96cd60603d8170 , < f7d53dd3f267e46a784f219a75072f2f400d42b9 (git)
Linux	Linux	Affected: 6.15 Unaffected: 0 , < 6.15 (semver) Unaffected: 6.18.49 , ≤ 6.18.* (semver) Unaffected: 7.1.13 , ≤ 7.1.* (semver) Unaffected: 7.2.3 , ≤ 7.2.* (semver) Unaffected: 7.3-rc1 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "crypto/krb5/krb5_api.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "731a5b6fb4c1705f9405d9029dd64ea81e336207",
              "status": "affected",
              "version": "3936f02bf2d3308a7359dd37dd96cd60603d8170",
              "versionType": "git"
            },
            {
              "lessThan": "91b96dc9cc250cd16751f53de525cf3442ca0962",
              "status": "affected",
              "version": "3936f02bf2d3308a7359dd37dd96cd60603d8170",
              "versionType": "git"
            },
            {
              "lessThan": "a1bf79365794783b19f5b09e8a23f7ee311e8931",
              "status": "affected",
              "version": "3936f02bf2d3308a7359dd37dd96cd60603d8170",
              "versionType": "git"
            },
            {
              "lessThan": "f7d53dd3f267e46a784f219a75072f2f400d42b9",
              "status": "affected",
              "version": "3936f02bf2d3308a7359dd37dd96cd60603d8170",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "crypto/krb5/krb5_api.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.15"
            },
            {
              "lessThan": "6.15",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.49",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.13",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.3",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3-rc1",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.49",
                  "versionStartIncluding": "6.15",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.13",
                  "versionStartIncluding": "6.15",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2.3",
                  "versionStartIncluding": "6.15",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3-rc1",
                  "versionStartIncluding": "6.15",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: krb5 - use kfree_sensitive() for derived key buffers\n\ncrypto_krb5_prepare_encryption() and crypto_krb5_prepare_checksum()\nfree the buffer holding the freshly derived keys with plain kfree(),\nleaving the key material behind in the freed slab object."
        }
      ],
      "metrics": [
        {
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            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - crypto_krb5_prepare_encryption() and crypto_krb5_prepare_checksum() run from nfsd RPCSEC_GSS on TCP/2049, from in-kernel RxGK handshake processing of remote RESPONSE packets (rxgk_extract_token/rxgk_set_up_token_cipher), and from Ceph/AFS network-filesystem security, so a remote peer can cause derived Kerberos keys to be left in freed slab.\nAC:L - Each prepare path derives Ke/Ki/Kc into a kmalloc buffer then frees it with plain kfree(); the leftover is deterministic on every GSS/RxGK/Ceph context setup, with no race or attacker-uncontrollable memory layout required to leave the keys in the slab.\nPR:N - RxGK token-cipher setup runs while decrypting the authentication token, before the token or authenticator is verified, and nfsd RPCSEC_GSS INIT is the authentication handshake; a network peer needs no local Linux account or capability to drive these pre-auth paths.\nUI:N - A Kerberos NFS server or RxRPC/AFS endpoint automatically processes incoming GSS/RxGK handshake packets; no victim mount, click, or other interactive action is required at exploit time.\nS:U - Leftover keys remain in host-kernel slab; this is ordinary kernel information disclosure within the same security authority, not a VM escape, IOMMU bypass, or sandbox breakout.\nC:H - The freed buffers hold complete derived Kerberos encryption and integrity keys (Ke/Ki/Kc, up to 32-byte AES-256 material). Recovering them from reused slab yields full session-key disclosure for NFS, AFS, Ceph, or RxGK traffic.\nI:N - The bug only fails to wipe key material before kfree(); it does not corrupt kernel memory, provide a write primitive, or hijack control flow.\nA:N - Replacing kfree() with kfree_sensitive() does not affect control flow; the plain kfree() path does not oops, deadlock, leak allocator objects, or otherwise impact availability."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-10T05:50:23.589Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/731a5b6fb4c1705f9405d9029dd64ea81e336207"
        },
        {
          "url": "https://git.kernel.org/stable/c/91b96dc9cc250cd16751f53de525cf3442ca0962"
        },
        {
          "url": "https://git.kernel.org/stable/c/a1bf79365794783b19f5b09e8a23f7ee311e8931"
        },
        {
          "url": "https://git.kernel.org/stable/c/f7d53dd3f267e46a784f219a75072f2f400d42b9"
        }
      ],
      "title": "crypto: krb5 - use kfree_sensitive() for derived key buffers",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-80924",
    "datePublished": "2026-09-09T16:19:44.150Z",
    "dateReserved": "2026-08-26T14:34:25.802Z",
    "dateUpdated": "2026-09-10T05:50:23.589Z",
    "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.

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GHSA-V3J5-MP2X-9859

CVE-2026-80924 (GCVE-0-2026-80924)

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Sightings

Nomenclature