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CVE-2025-21966 (GCVE-0-2025-21966)

Vulnerability from cvelistv5 – Published: 2025-04-01 15:47 – Updated: 2026-08-05 11:55
VLAI
Title
dm-flakey: Fix memory corruption in optional corrupt_bio_byte feature
Summary
In the Linux kernel, the following vulnerability has been resolved: dm-flakey: Fix memory corruption in optional corrupt_bio_byte feature Fix memory corruption due to incorrect parameter being passed to bio_init
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-10-01 18:16 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 1d9a943898533e83f20370c0e1448d606627522e , < 818330f756f3800c37d738bd36bce60eac949938 (git)
Affected: 1d9a943898533e83f20370c0e1448d606627522e , < 5a87e46da2418c57b445371f5ca0958d5779ba5f (git)
Affected: 1d9a943898533e83f20370c0e1448d606627522e , < da070843e153471be4297a12fdaa64023276f40e (git)
Affected: 1d9a943898533e83f20370c0e1448d606627522e , < 57e9417f69839cb10f7ffca684c38acd28ceb57b (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.5
Unaffected: 0 , < 6.5 (semver)
Unaffected: 6.6.84 , ≤ 6.6.* (semver)
Unaffected: 6.12.20 , ≤ 6.12.* (semver)
Unaffected: 6.13.8 , ≤ 6.13.* (semver)
Unaffected: 6.14 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
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      "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-2025-21966\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2025-10-01T18:16:20.613850Z\"}}}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-787\", \"description\": \"CWE-787 Out-of-bounds Write\"}]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2025-10-01T14:38:38.990Z\"}}], \"cna\": {\"title\": \"dm-flakey: Fix memory corruption in optional corrupt_bio_byte feature\", \"metrics\": [{\"cvssV3_1\": {\"version\": \"3.1\", \"baseScore\": 7.8, \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"AV:L - The corruption is triggered by write I/O submitted locally to a dm-flakey block device or a filesystem mounted on it; there is no remote or network-facing path into drivers/md/dm-flakey.c.\\nAC:L - Once the target is configured, every matching write bio during the down interval deterministically overflows the neighbouring slab object \\u2014 no race to win and the up/down cycle is periodic and predictable, so the attacker simply writes or retries.\\nPR:L - Creating the dm-flakey table needs CAP_SYS_ADMIN, but on the systems where this feature is actually deployed (fstests/CI/QA fault-injection hosts) any unprivileged user with write access to the device or its mounted filesystem triggers the out-of-bounds write with ordinary writes.\\nUI:N - The attacker\u0027s own writes drive the corruption; no action by another user or administrator is needed beyond the pre-existing device configuration.\\nS:U - The out-of-bounds write corrupts kernel slab memory within the same kernel security authority; no VM, IOMMU, or sandbox boundary is crossed.\\nC:H - The clone\u0027s bvec array aliases memory outside the original bio\u0027s allocation, and the subsequent `bio_for_each_folio_all()`/`folio_put()` walk reads back whatever now occupies that neighbouring live object, giving a controlled heap corruption primitive usable for arbitrary kernel memory disclosure.\\nI:H - This is a direct heap out-of-bounds write of `struct bio_vec` records (page pointer, length, offset) into adjacent slab objects \\u2014 from 16 bytes up to ~16 KB under attacker-inducible allocation-order fallback \\u2014 a classic exploitable primitive for pointer corruption and control-flow hijack.\\nA:H - Corrupting adjacent `dm_io`/`dm_target_io`/bio structures and calling `folio_put()` on garbage pointers reliably produces oopses, BUG_ONs, and page refcount corruption leading to kernel panic.\"}]}], \"affected\": [{\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"1d9a943898533e83f20370c0e1448d606627522e\", \"lessThan\": \"818330f756f3800c37d738bd36bce60eac949938\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"1d9a943898533e83f20370c0e1448d606627522e\", \"lessThan\": \"5a87e46da2418c57b445371f5ca0958d5779ba5f\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"1d9a943898533e83f20370c0e1448d606627522e\", \"lessThan\": \"da070843e153471be4297a12fdaa64023276f40e\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"1d9a943898533e83f20370c0e1448d606627522e\", \"lessThan\": \"57e9417f69839cb10f7ffca684c38acd28ceb57b\", \"versionType\": \"git\"}], \"programFiles\": [\"drivers/md/dm-flakey.c\"], \"defaultStatus\": \"unaffected\"}, {\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"6.5\"}, {\"status\": \"unaffected\", \"version\": \"0\", \"lessThan\": \"6.5\", \"versionType\": \"semver\"}, {\"status\": \"unaffected\", \"version\": \"6.6.84\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.6.*\"}, {\"status\": \"unaffected\", \"version\": \"6.12.20\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.12.*\"}, {\"status\": \"unaffected\", \"version\": \"6.13.8\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.13.*\"}, {\"status\": \"unaffected\", \"version\": \"6.14\", \"versionType\": \"original_commit_for_fix\", \"lessThanOrEqual\": \"*\"}], \"programFiles\": [\"drivers/md/dm-flakey.c\"], \"defaultStatus\": \"affected\"}], \"references\": [{\"url\": \"https://git.kernel.org/stable/c/818330f756f3800c37d738bd36bce60eac949938\"}, {\"url\": \"https://git.kernel.org/stable/c/5a87e46da2418c57b445371f5ca0958d5779ba5f\"}, {\"url\": \"https://git.kernel.org/stable/c/da070843e153471be4297a12fdaa64023276f40e\"}, {\"url\": \"https://git.kernel.org/stable/c/57e9417f69839cb10f7ffca684c38acd28ceb57b\"}], \"x_generator\": {\"engine\": \"bippy-1.2.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"In the Linux kernel, the following vulnerability has been resolved:\\n\\ndm-flakey: Fix memory corruption in optional corrupt_bio_byte feature\\n\\nFix memory corruption due to incorrect parameter being passed to bio_init\"}], \"cpeApplicability\": [{\"nodes\": [{\"negate\": false, \"cpeMatch\": [{\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.6.84\", \"versionStartIncluding\": \"6.5\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.12.20\", \"versionStartIncluding\": \"6.5\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.13.8\", \"versionStartIncluding\": \"6.5\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.14\", \"versionStartIncluding\": \"6.5\"}], \"operator\": \"OR\"}]}], \"providerMetadata\": {\"orgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"shortName\": \"Linux\", \"dateUpdated\": \"2026-08-05T11:55:42.212Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2025-21966\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-08-05T11:55:42.212Z\", \"dateReserved\": \"2024-12-29T08:45:45.796Z\", \"assignerOrgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"datePublished\": \"2025-04-01T15:47:01.836Z\", \"assignerShortName\": \"Linux\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



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Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.