CVE-2025-21893 (GCVE-0-2025-21893)

Vulnerability from cvelistv5 – Published: 2025-03-31 19:41 – Updated: 2025-05-04 07:23
VLAI?
Summary
In the Linux kernel, the following vulnerability has been resolved: keys: Fix UAF in key_put() Once a key's reference count has been reduced to 0, the garbage collector thread may destroy it at any time and so key_put() is not allowed to touch the key after that point. The most key_put() is normally allowed to do is to touch key_gc_work as that's a static global variable. However, in an effort to speed up the reclamation of quota, this is now done in key_put() once the key's usage is reduced to 0 - but now the code is looking at the key after the deadline, which is forbidden. Fix this by using a flag to indicate that a key can be gc'd now rather than looking at the key's refcount in the garbage collector.
Severity ?
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 9578e327b2b4935a25d49e3891b8fcca9b6c10c6 , < 6afe2ea2daec156bd94ad2c5a6f4f4c48240dcd3 (git)
Affected: 9578e327b2b4935a25d49e3891b8fcca9b6c10c6 , < f6a3cf833188e897c97028cd7b926e3f2cb1a8c0 (git)
Affected: 9578e327b2b4935a25d49e3891b8fcca9b6c10c6 , < 75845c6c1a64483e9985302793dbf0dfa5f71e32 (git)
Create a notification for this product.
    Linux Linux Affected: 6.10
Unaffected: 0 , < 6.10 (semver)
Unaffected: 6.12.21 , ≤ 6.12.* (semver)
Unaffected: 6.13.9 , ≤ 6.13.* (semver)
Unaffected: 6.14 , ≤ * (original_commit_for_fix)
Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "LOCAL",
              "availabilityImpact": "HIGH",
              "baseScore": 7.8,
              "baseSeverity": "HIGH",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "HIGH",
              "privilegesRequired": "LOW",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2025-21893",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-03-31T20:45:39.862234Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-416",
                "description": "CWE-416 Use After Free",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-03-31T20:53:50.193Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "include/linux/key.h",
            "security/keys/gc.c",
            "security/keys/key.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "6afe2ea2daec156bd94ad2c5a6f4f4c48240dcd3",
              "status": "affected",
              "version": "9578e327b2b4935a25d49e3891b8fcca9b6c10c6",
              "versionType": "git"
            },
            {
              "lessThan": "f6a3cf833188e897c97028cd7b926e3f2cb1a8c0",
              "status": "affected",
              "version": "9578e327b2b4935a25d49e3891b8fcca9b6c10c6",
              "versionType": "git"
            },
            {
              "lessThan": "75845c6c1a64483e9985302793dbf0dfa5f71e32",
              "status": "affected",
              "version": "9578e327b2b4935a25d49e3891b8fcca9b6c10c6",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "include/linux/key.h",
            "security/keys/gc.c",
            "security/keys/key.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.10"
            },
            {
              "lessThan": "6.10",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.21",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.13.*",
              "status": "unaffected",
              "version": "6.13.9",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.14",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.21",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.13.9",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.14",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nkeys: Fix UAF in key_put()\n\nOnce a key\u0027s reference count has been reduced to 0, the garbage collector\nthread may destroy it at any time and so key_put() is not allowed to touch\nthe key after that point.  The most key_put() is normally allowed to do is\nto touch key_gc_work as that\u0027s a static global variable.\n\nHowever, in an effort to speed up the reclamation of quota, this is now\ndone in key_put() once the key\u0027s usage is reduced to 0 - but now the code\nis looking at the key after the deadline, which is forbidden.\n\nFix this by using a flag to indicate that a key can be gc\u0027d now rather than\nlooking at the key\u0027s refcount in the garbage collector."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2025-05-04T07:23:40.081Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/6afe2ea2daec156bd94ad2c5a6f4f4c48240dcd3"
        },
        {
          "url": "https://git.kernel.org/stable/c/f6a3cf833188e897c97028cd7b926e3f2cb1a8c0"
        },
        {
          "url": "https://git.kernel.org/stable/c/75845c6c1a64483e9985302793dbf0dfa5f71e32"
        }
      ],
      "title": "keys: Fix UAF in key_put()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-21893",
    "datePublished": "2025-03-31T19:41:46.137Z",
    "dateReserved": "2024-12-29T08:45:45.783Z",
    "dateUpdated": "2025-05-04T07:23:40.081Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1",
  "vulnerability-lookup:meta": {
    "nvd": "{\"cve\":{\"id\":\"CVE-2025-21893\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2025-03-31T20:15:14.613\",\"lastModified\":\"2025-04-08T15:48:59.010\",\"vulnStatus\":\"Analyzed\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nkeys: Fix UAF in key_put()\\n\\nOnce a key\u0027s reference count has been reduced to 0, the garbage collector\\nthread may destroy it at any time and so key_put() is not allowed to touch\\nthe key after that point.  The most key_put() is normally allowed to do is\\nto touch key_gc_work as that\u0027s a static global variable.\\n\\nHowever, in an effort to speed up the reclamation of quota, this is now\\ndone in key_put() once the key\u0027s usage is reduced to 0 - but now the code\\nis looking at the key after the deadline, which is forbidden.\\n\\nFix this by using a flag to indicate that a key can be gc\u0027d now rather than\\nlooking at the key\u0027s refcount in the garbage collector.\"},{\"lang\":\"es\",\"value\":\"En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: keys: Fix UAF en key_put() Una vez que el recuento de referencia de una clave se ha reducido a 0, el hilo del recolector de basura puede destruirla en cualquier momento y, por lo tanto, key_put() no puede tocar la clave despu\u00e9s de ese punto. Lo m\u00e1ximo que key_put() normalmente puede hacer es tocar key_gc_work ya que es una variable global est\u00e1tica. Sin embargo, en un esfuerzo por acelerar la recuperaci\u00f3n de la cuota, esto ahora se hace en key_put() una vez que el uso de la clave se reduce a 0, pero ahora el c\u00f3digo mira la clave despu\u00e9s de la fecha l\u00edmite, lo cual est\u00e1 prohibido. Corrija esto usando una bandera para indicar que una clave puede ser gc\u0027d ahora en lugar de mirar el recuento de referencia de la clave en el recolector de basura.\"}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":7.8,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":5.9}]},\"weaknesses\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-416\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.10\",\"versionEndExcluding\":\"6.12.21\",\"matchCriteriaId\":\"2D7E688A-00BB-4090-BC53-2B56AE5873B7\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.13\",\"versionEndExcluding\":\"6.13.9\",\"matchCriteriaId\":\"FAECBE4D-58CF-4836-BBAB-5E28B800A778\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:*\",\"matchCriteriaId\":\"186716B6-2B66-4BD0-852E-D48E71C0C85F\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:*\",\"matchCriteriaId\":\"0D3E781C-403A-498F-9DA9-ECEE50F41E75\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:*\",\"matchCriteriaId\":\"66619FB8-0AAF-4166-B2CF-67B24143261D\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.14:rc4:*:*:*:*:*:*\",\"matchCriteriaId\":\"D3D6550E-6679-4560-902D-AF52DCFE905B\"}]}]}],\"references\":[{\"url\":\"https://git.kernel.org/stable/c/6afe2ea2daec156bd94ad2c5a6f4f4c48240dcd3\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/75845c6c1a64483e9985302793dbf0dfa5f71e32\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/f6a3cf833188e897c97028cd7b926e3f2cb1a8c0\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]}]}}",
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 7.8, \"attackVector\": \"LOCAL\", \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\", \"integrityImpact\": \"HIGH\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"HIGH\", \"privilegesRequired\": \"LOW\", \"confidentialityImpact\": \"HIGH\"}}, {\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2025-21893\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2025-03-31T20:45:39.862234Z\"}}}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-416\", \"description\": \"CWE-416 Use After Free\"}]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2025-03-31T20:45:41.300Z\"}}], \"cna\": {\"title\": \"keys: Fix UAF in key_put()\", \"affected\": [{\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"9578e327b2b4935a25d49e3891b8fcca9b6c10c6\", \"lessThan\": \"6afe2ea2daec156bd94ad2c5a6f4f4c48240dcd3\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"9578e327b2b4935a25d49e3891b8fcca9b6c10c6\", \"lessThan\": \"f6a3cf833188e897c97028cd7b926e3f2cb1a8c0\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"9578e327b2b4935a25d49e3891b8fcca9b6c10c6\", \"lessThan\": \"75845c6c1a64483e9985302793dbf0dfa5f71e32\", \"versionType\": \"git\"}], \"programFiles\": [\"include/linux/key.h\", \"security/keys/gc.c\", \"security/keys/key.c\"], \"defaultStatus\": \"unaffected\"}, {\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"6.10\"}, {\"status\": \"unaffected\", \"version\": \"0\", \"lessThan\": \"6.10\", \"versionType\": \"semver\"}, {\"status\": \"unaffected\", \"version\": \"6.12.21\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.12.*\"}, {\"status\": \"unaffected\", \"version\": \"6.13.9\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.13.*\"}, {\"status\": \"unaffected\", \"version\": \"6.14\", \"versionType\": \"original_commit_for_fix\", \"lessThanOrEqual\": \"*\"}], \"programFiles\": [\"include/linux/key.h\", \"security/keys/gc.c\", \"security/keys/key.c\"], \"defaultStatus\": \"affected\"}], \"references\": [{\"url\": \"https://git.kernel.org/stable/c/6afe2ea2daec156bd94ad2c5a6f4f4c48240dcd3\"}, {\"url\": \"https://git.kernel.org/stable/c/f6a3cf833188e897c97028cd7b926e3f2cb1a8c0\"}, {\"url\": \"https://git.kernel.org/stable/c/75845c6c1a64483e9985302793dbf0dfa5f71e32\"}], \"x_generator\": {\"engine\": \"bippy-7c5fe7eed585\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"In the Linux kernel, the following vulnerability has been resolved:\\n\\nkeys: Fix UAF in key_put()\\n\\nOnce a key\u0027s reference count has been reduced to 0, the garbage collector\\nthread may destroy it at any time and so key_put() is not allowed to touch\\nthe key after that point.  The most key_put() is normally allowed to do is\\nto touch key_gc_work as that\u0027s a static global variable.\\n\\nHowever, in an effort to speed up the reclamation of quota, this is now\\ndone in key_put() once the key\u0027s usage is reduced to 0 - but now the code\\nis looking at the key after the deadline, which is forbidden.\\n\\nFix this by using a flag to indicate that a key can be gc\u0027d now rather than\\nlooking at the key\u0027s refcount in the garbage collector.\"}], \"providerMetadata\": {\"orgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"shortName\": \"Linux\", \"dateUpdated\": \"2025-03-31T19:41:46.137Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2025-21893\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2025-03-31T20:53:50.193Z\", \"dateReserved\": \"2024-12-29T08:45:45.783Z\", \"assignerOrgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"datePublished\": \"2025-03-31T19:41:46.137Z\", \"assignerShortName\": \"Linux\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.1"
    }
  }
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

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.