CVE-2025-39877

{"id": "CVE-2025-39877", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2025-39877", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-11-05T21:12:49.483083Z"}}], "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}]}, "affected": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "affectedData": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "a61ea561c87139992fe32afdee48a6f6b85d824a", "lessThan": "3858c44341ad49dc7544b19cc9f9ecffaa7cc50e", "versionType": "git"}, {"status": "affected", "version": "a61ea561c87139992fe32afdee48a6f6b85d824a", "lessThan": "60d7a3d2b985a395318faa1d88da6915fad11c19", "versionType": "git"}, {"status": "affected", "version": "a61ea561c87139992fe32afdee48a6f6b85d824a", "lessThan": "26d29b2ac87a2989071755f9828ebf839b560d4c", "versionType": "git"}, {"status": "affected", "version": "a61ea561c87139992fe32afdee48a6f6b85d824a", "lessThan": "4e87f461d61959647464a94d11ae15c011be58ce", "versionType": "git"}, {"status": "affected", "version": "a61ea561c87139992fe32afdee48a6f6b85d824a", "lessThan": "3260a3f0828e06f5f13fac69fb1999a6d60d9cff", "versionType": "git"}], "programFiles": ["mm/damon/sysfs.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "5.18"}, {"status": "unaffected", "version": "0", "lessThan": "5.18", "versionType": "semver"}, {"status": "unaffected", "version": "6.1.153", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"status": "unaffected", "version": "6.6.107", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.12.48", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.16.8", "versionType": "semver", "lessThanOrEqual": "6.16.*"}, {"status": "unaffected", "version": "6.17", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["mm/damon/sysfs.c"], "defaultStatus": "affected"}]}], "published": "2025-09-23T06:15:47.230", "references": [{"url": "https://git.kernel.org/stable/c/26d29b2ac87a2989071755f9828ebf839b560d4c", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/3260a3f0828e06f5f13fac69fb1999a6d60d9cff", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/3858c44341ad49dc7544b19cc9f9ecffaa7cc50e", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/4e87f461d61959647464a94d11ae15c011be58ce", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/60d7a3d2b985a395318faa1d88da6915fad11c19", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html", "tags": ["Mailing List", "Third Party Advisory"], "source": "af854a3a-2127-422b-91ae-364da2661108"}], "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/sysfs: fix use-after-free in state_show()\n\nstate_show() reads kdamond->damon_ctx without holding damon_sysfs_lock. \nThis allows a use-after-free race:\n\nCPU 0 CPU 1\n----- -----\nstate_show() damon_sysfs_turn_damon_on()\nctx = kdamond->damon_ctx; mutex_lock(&damon_sysfs_lock);\n damon_destroy_ctx(kdamond->damon_ctx);\n kdamond->damon_ctx = NULL;\n mutex_unlock(&damon_sysfs_lock);\ndamon_is_running(ctx); /* ctx is freed */\nmutex_lock(&ctx->kdamond_lock); /* UAF */\n\n(The race can also occur with damon_sysfs_kdamonds_rm_dirs() and\ndamon_sysfs_kdamond_release(), which free or replace the context under\ndamon_sysfs_lock.)\n\nFix by taking damon_sysfs_lock before dereferencing the context, mirroring\nthe locking used in pid_show().\n\nThe bug has existed since state_show() first accessed kdamond->damon_ctx."}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nmm/damon/sysfs: corregir uso despu\u00e9s de liberaci\u00f3n en state_show()\n\nstate_show() lee kdamond->damon_ctx sin mantener damon_sysfs_lock. Esto permite una condici\u00f3n de carrera de uso despu\u00e9s de liberaci\u00f3n:\n\nCPU 0 CPU 1\n----- -----\nstate_show() damon_sysfs_turn_damon_on()\nctx = kdamond->damon_ctx; mutex_lock(&damon_sysfs_lock);\n damon_destroy_ctx(kdamond->damon_ctx);\n kdamond->damon_ctx = NULL;\n mutex_unlock(&damon_sysfs_lock);\ndamon_is_running(ctx); /* ctx es liberado */\nmutex_lock(&ctx->kdamond_lock); /* UAF */\n\n(La condici\u00f3n de carrera tambi\u00e9n puede ocurrir con damon_sysfs_kdamonds_rm_dirs() y damon_sysfs_kdamond_release(), que liberan o reemplazan el contexto bajo damon_sysfs_lock.)\n\nSoluci\u00f3n al tomar damon_sysfs_lock antes de desreferenciar el contexto, replicando el bloqueo utilizado en pid_show().\n\nEl error ha existido desde que state_show() accedi\u00f3 por primera vez a kdamond->damon_ctx."}], "lastModified": "2026-11-05T22:17:34.610", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "7476DB08-58FC-455C-BA35-27E13002B258", "versionEndExcluding": "6.1.153", "versionStartIncluding": "5.18"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "D273EDA6-2CFE-4EBD-B024-62EB057830F3", "versionEndExcluding": "6.6.107", "versionStartIncluding": "6.2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "9652E701-5C8E-49CF-89A5-499E214A5902", "versionEndExcluding": "6.12.48", "versionStartIncluding": "6.7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "8DA00A4E-AABB-4A69-AB39-67B22D0B36D2", "versionEndExcluding": "6.16.8", "versionStartIncluding": "6.13"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "327D22EF-390B-454C-BD31-2ED23C998A1C"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "C730CD9A-D969-4A8E-9522-162AAF7C0EE9"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc3:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "39982C4B-716E-4B2F-8196-FA301F47807D"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc4:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "340BEEA9-D70D-4290-B502-FBB1032353B1"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc5:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "47E4C5C0-079F-4838-971B-8C503D48FCC2"}], "operator": "OR"}]}, {"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "FA6FEEC2-9F11-4643-8827-749718254FED"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}