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CVE-2026-99225

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: keys: Check the authorization payload in process keyring searches An authorization payload and its saved credentials must remain valid while search_process_keyrings_rcu() searches the requestor's keyrings. The function validates the authorization key, then separately loads payload.data[0] and unconditionally reads rka->cred. Validation does not prevent request_key_auth_revoke() from clearing the payload. A request-key helper can assume authority and fork a descendant that inherits the authorization key. If the descendant misses in its own keyrings, it falls back to the saved requestor credentials. Successful target instantiation invalidates the authorization key without clearing the payload. After the helper exits, UMH_WAIT_PROC returns to the requester, which calls complete_request_key() and revokes that key. With the descendant paused after validation, the paths can interleave as follows: 1. The descendant enters search_process_keyrings_rcu() under RCU and key_validate() succeeds. 2. The helper instantiates the target, invalidates the authorization key, and exits. 3. The requester resumes from UMH_WAIT_PROC, calls complete_request_key(), and revokes the authorization key. request_key_auth_revoke() sets its payload pointer to NULL. 4. The descendant loads NULL and dereferences rka->cred. This NULL dereference can oops the kernel. RCU delays payload disposal but does not prevent the pointer from being cleared. Load the payload with dereference_key_rcu() and require a non-NULL result before validating the authorization key and searching its saved credentials. A non-NULL payload and its credentials remain alive for the caller's RCU read-side section; a cleared payload skips the fallback search and follows the existing error selection. KASAN report as below: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f] RIP: 0010:search_process_keyrings_rcu+0x32b/0x790

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-11-02 16:17:47.047000
Last modified
2026-11-02 16:17:47.047000
View original CVE JSON
{
  "id": "CVE-2026-99225",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-11-02T16:17:47.047",
  "lastModified": "2026-11-02T16:17:47.047",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nkeys: Check the authorization payload in process keyring searches\n\nAn authorization payload and its saved credentials must remain valid\nwhile search_process_keyrings_rcu() searches the requestor's keyrings.\nThe function validates the authorization key, then separately loads\npayload.data[0] and unconditionally reads rka->cred. Validation does\nnot prevent request_key_auth_revoke() from clearing the payload.\n\nA request-key helper can assume authority and fork a descendant that\ninherits the authorization key. If the descendant misses in its own\nkeyrings, it falls back to the saved requestor credentials. Successful\ntarget instantiation invalidates the authorization key without clearing\nthe payload. After the helper exits, UMH_WAIT_PROC returns to the\nrequester, which calls complete_request_key() and revokes that key.\n\nWith the descendant paused after validation, the paths can interleave\nas follows:\n\n  1. The descendant enters search_process_keyrings_rcu() under RCU and\n     key_validate() succeeds.\n  2. The helper instantiates the target, invalidates the authorization\n     key, and exits.\n  3. The requester resumes from UMH_WAIT_PROC, calls\n     complete_request_key(), and revokes the authorization key.\n     request_key_auth_revoke() sets its payload pointer to NULL.\n  4. The descendant loads NULL and dereferences rka->cred.\n\nThis NULL dereference can oops the kernel. RCU delays payload disposal\nbut does not prevent the pointer from being cleared.\n\nLoad the payload with dereference_key_rcu() and require a non-NULL\nresult before validating the authorization key and searching its saved\ncredentials. A non-NULL payload and its credentials remain alive for\nthe caller's RCU read-side section; a cleared payload skips the fallback\nsearch and follows the existing error selection.\n\nKASAN report as below:\n\n    Oops: general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] SMP KASAN NOPTI\n    KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f]\n    RIP: 0010:search_process_keyrings_rcu+0x32b/0x790"
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "security/keys/process_keys.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "e59428f721ee096d8a020504ea908a6f0d952735",
              "lessThan": "14fb6fad526b35a7ebd121f1dd313abe652e0aa6",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "e59428f721ee096d8a020504ea908a6f0d952735",
              "lessThan": "458cf9715af6aff3ac8d2ec60bd59e9d6236fd0f",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "e59428f721ee096d8a020504ea908a6f0d952735",
              "lessThan": "7d3d2fffe933e538472ccafe5bbc7109488b9ce3",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "e59428f721ee096d8a020504ea908a6f0d952735",
              "lessThan": "26949c2e4c461e9e620e935bc22717f36a40b615",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "e59428f721ee096d8a020504ea908a6f0d952735",
              "lessThan": "984a178d54515779a1bee100b92a6cee8777c830",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "e59428f721ee096d8a020504ea908a6f0d952735",
              "lessThan": "b86db7993051d05810601654e886a1e78e1fa495",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "e59428f721ee096d8a020504ea908a6f0d952735",
              "lessThan": "b4dfda438fee3c6faa15d9b421c373de6a0e476f",
              "versionType": "git",
              "status": "affected"
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            {
              "version": "e59428f721ee096d8a020504ea908a6f0d952735",
              "lessThan": "49f4e768540d25d8852ef750313afda6a4774871",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "security/keys/process_keys.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "5.3",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "5.3",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.10.273",
              "lessThanOrEqual": "5.10.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.15.224",
              "lessThanOrEqual": "5.15.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.191",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.161",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.115",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.60",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.14",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3.1",
              "lessThanOrEqual": "7.3.*",
              "versionType": "semver",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/14fb6fad526b35a7ebd121f1dd313abe652e0aa6",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/26949c2e4c461e9e620e935bc22717f36a40b615",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/458cf9715af6aff3ac8d2ec60bd59e9d6236fd0f",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/49f4e768540d25d8852ef750313afda6a4774871",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/7d3d2fffe933e538472ccafe5bbc7109488b9ce3",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/984a178d54515779a1bee100b92a6cee8777c830",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b4dfda438fee3c6faa15d9b421c373de6a0e476f",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b86db7993051d05810601654e886a1e78e1fa495",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}