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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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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.


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.