CVE-2026-64418

{"id": "CVE-2026-64418", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Secondary", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "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": "307bececcd1205bcb67a3c0d53a69db237ccc9d4", "lessThan": "b9a280a9a454ed514636351d53fe2a233dc5054b", "versionType": "git"}, {"status": "affected", "version": "307bececcd1205bcb67a3c0d53a69db237ccc9d4", "lessThan": "6465ff3ce65131c774a312d450abe10f4b9f3875", "versionType": "git"}, {"status": "affected", "version": "307bececcd1205bcb67a3c0d53a69db237ccc9d4", "lessThan": "284c267f013e45d8c89d9fb9373105dc8e6c0947", "versionType": "git"}, {"status": "affected", "version": "307bececcd1205bcb67a3c0d53a69db237ccc9d4", "lessThan": "65476d31d8056e859c48580f82295ce159196ffe", "versionType": "git"}], "programFiles": ["mm/shrinker.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "6.7"}, {"status": "unaffected", "version": "0", "lessThan": "6.7", "versionType": "semver"}, {"status": "unaffected", "version": "6.12.96", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.18.39", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "7.1.4", "versionType": "semver", "lessThanOrEqual": "7.1.*"}, {"status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["mm/shrinker.c"], "defaultStatus": "affected"}]}], "published": "2026-07-25T10:17:25.727", "references": [{"url": "https://git.kernel.org/stable/c/284c267f013e45d8c89d9fb9373105dc8e6c0947", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/6465ff3ce65131c774a312d450abe10f4b9f3875", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/65476d31d8056e859c48580f82295ce159196ffe", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/b9a280a9a454ed514636351d53fe2a233dc5054b", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-362"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm: shrinker: fix shrinker_info teardown race with expansion\n\nexpand_shrinker_info() iterates all visible memcgs under shrinker_mutex,\nincluding memcgs that have not finished ->css_online() yet.\n\nOnce pn->shrinker_info has been published, teardown must stay serialized\nwith expand_shrinker_info() until that memcg is either fully online or no\nlonger visible to iteration. Today alloc_shrinker_info() breaks that rule\nby dropping shrinker_mutex before freeing a partially initialized\nshrinker_info array, which may cause the following race:\n\nCPU0 CPU1\n==== ====\n\ncss_create\n--> list_add_tail_rcu(&css->sibling, &parent_css->children);\n online_css\n --> mem_cgroup_css_online\n --> alloc_shrinker_info\n --> alloc node0 info\n rcu_assign_pointer(C->node0->shrinker_info, old0)\n alloc node1 info -> FAIL -> goto err\n mutex_unlock(shrinker_mutex)\n\n shrinker_alloc()\n --> shrinker_memcg_alloc\n --> mutex_lock(shrinker_mutex)\n expand_shrinker_info\n --> mem_cgroup_iter see the memcg\n expand_one_shrinker_info\n --> old0 = C->node0->shrinker_info\n memcpy(new->unit, old0->unit, ...);\n\n free_shrinker_info\n --> kvfree(old0);\n\n /* double free !! */\n kvfree_rcu(old0, rcu);\n\nThe same problem exists later in mem_cgroup_css_online(). If\nalloc_shrinker_info() succeeds but a subsequent objcg allocation fails,\nthe free_objcg -> free_shrinker_info() unwind path tears down the already\npublished pn->shrinker_info arrays without shrinker_mutex. The\nexpand_one_shrinker_info() can race with that teardown in the same way,\nleading to use-after-free or double-free of the old shrinker_info.\n\nFix this by serializing shrinker_info teardown with shrinker_mutex, and by\nkeeping alloc_shrinker_info() error cleanup inside the locked section."}], "lastModified": "2026-09-04T15:24:49.577", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "38A8100E-2B1A-462F-AEE9-8901B870FEF2", "versionEndExcluding": "6.12.96", "versionStartIncluding": "6.7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "914AE4BC-3D59-4C5A-9DB5-9CE327B429F7", "versionEndExcluding": "6.18.39", "versionStartIncluding": "6.13"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "6228DDD6-4557-4AA3-9F43-AB995D471E42", "versionEndExcluding": "7.1.4", "versionStartIncluding": "6.19"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.2:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "5E8B9085-7ADB-4A05-89EF-12949B6A0509"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.2:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "1FC0D50D-9D58-4947-A197-A5A3FF07E7E3"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}