CVE-2026-43388

{"id": "CVE-2026-43388", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"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"}, "impactScore": 5.9, "exploitabilityScore": 1.8}]}, "published": "2026-05-08T15:16:50.180", "references": [{"url": "https://git.kernel.org/stable/c/9320c77134ab8d7701e20608bbf08517df4fa321", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/ce0aa47c963b8c3e5beace89e2b5a665a64b5b6b", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/d210fdcac9c0d1380eab448aebc93f602c1cd4e6", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-416"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/damon/core: clear walk_control on inactive context in damos_walk()\n\ndamos_walk() sets ctx->walk_control to the caller-provided control\nstructure before checking whether the context is running. If the context\nis inactive (damon_is_running() returns false), the function returns\n-EINVAL without clearing ctx->walk_control. This leaves a dangling\npointer to a stack-allocated structure that will be freed when the caller\nreturns.\n\nThis is structurally identical to the bug fixed in commit f9132fbc2e83\n(\"mm/damon/core: remove call_control in inactive contexts\") for\ndamon_call(), which had the same pattern of linking a control object and\nreturning an error without unlinking it.\n\nThe dangling walk_control pointer can cause:\n1. Use-after-free if the context is later started and kdamond\n\u00a0 \u00a0dereferences ctx->walk_control (e.g., in damos_walk_cancel()\n\u00a0 \u00a0which writes to control->canceled and calls complete())\n2. Permanent -EBUSY from subsequent damos_walk() calls, since the\n\u00a0 \u00a0stale pointer is non-NULL\n\nNonetheless, the real user impact is quite restrictive. The\nuse-after-free is impossible because there is no damos_walk() callers who\nstarts the context later. The permanent -EBUSY can actually confuse\nusers, as DAMON is not running. But the symptom is kept only while the\ncontext is turned off. Turning it on again will make DAMON internally\nuses a newly generated damon_ctx object that doesn't have the invalid\ndamos_walk_control pointer, so everything will work fine again.\n\nFix this by clearing ctx->walk_control under walk_control_lock before\nreturning -EINVAL, mirroring the fix pattern from f9132fbc2e83."}], "lastModified": "2026-05-26T15:03:21.240", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "7484E98E-61F0-4DCE-9DBF-83D2F75F99EB", "versionEndExcluding": "6.18.19", "versionStartIncluding": "6.14"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "E825E7C3-FEAC-4FD3-8A81-78D7387948C9", "versionEndExcluding": "6.19.9", "versionStartIncluding": "6.19"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F253B622-8837-4245-BCE5-A7BF8FC76A16"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F666C8D8-6538-46D4-B318-87610DE64C34"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}