{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-64015", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T07:54:57.027Z", "datePublished": "2026-07-19T15:39:10.557Z", "dateUpdated": "2026-08-05T12:38:12.353Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:38:12.353Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsecurity/keys: fix missed RCU read section on lookup\n\nNicholas Carlini reports that the keyring code calls assoc_array_find()\nin find_key_to_update() without holding the RCU read lock, while the\nassoc_array_gc() code really is designed around removing the node from\nthe tree and then freeing it after an RCU grace-period.\n\nThe regular key handling doesn't see this because holding the keyring\nsemaphore hides any lifetime issues, but the persistent key handling\nuses a different model.\n\nInstead of extending the keyring locking, just do the simple RCU locking\nthat the assoc_array was designed for." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The bug is reached only through find_key_to_update() on the persistent keyring register, which is invoked from keyctl_get_persistent() via the keyctl(2) syscall. There is no network, adjacent-radio, or physical-device path to this code.\nAC:L - Exploitation is a race between assoc_array_find() and assoc_array_gc() on the .persistent_register keyring; the attacker controls both sides by repeatedly calling KEYCTL_GET_PERSISTENT (including from multiple threads) while driving key expiry/GC via keyctl timeouts or natural garbage collection. Per kernel guidance, attacker-controlled races are AC:L.\nPR:L - Any unprivileged local user who can invoke keyctl() can call KEYCTL_GET_PERSISTENT for their own UID (-1) with a writable destination keyring (e.g., session keyring). No real-root or CAP_SETUID capability is required for the vulnerable lookup path; this remains PR:L even inside user namespaces.\nUI:N - Exploitation requires only the attacker's own keyctl syscalls and does not depend on any victim user action such as mounting a filesystem or opening a file.\nS:U - Impact is confined to kernel memory corruption and privilege escalation within the same kernel security domain; it does not cross a VM, container, or IOMMU boundary on its own.\nC:H - assoc_array_find() is documented to require an RCU read lock, but the persistent-keyring path called it without one while assoc_array_gc() frees tree nodes via call_rcu(), yielding a use-after-free on assoc_array nodes/leaves. UAF on kernel heap objects can be turned into arbitrary kernel memory reads.\nI:H - The freed assoc_array nodes can be reallocated and corrupted through concurrent GC versus lookup, providing a standard kernel heap UAF primitive that can be developed into arbitrary write or code-execution primitives.\nA:H - Dereferencing RCU-freed assoc_array tree nodes during lookup can cause kernel oops/panic from invalid pointer access, and UAF exploitation commonly destabilizes or crashes the kernel even when full exploitation is not attempted." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "security/keys/keyring.c" ], "versions": [ { "version": "b2a4df200d570b2c33a57e1ebfa5896e4bc81b69", "lessThan": "4c5d407ba3ff7f30561ff73ba1b07ed70c864edc", "status": "affected", "versionType": "git" }, { "version": "b2a4df200d570b2c33a57e1ebfa5896e4bc81b69", "lessThan": "cefa4265b11176c897a7d9e8e54d89e3701c5584", "status": "affected", "versionType": "git" }, { "version": "b2a4df200d570b2c33a57e1ebfa5896e4bc81b69", "lessThan": "5659e6923cb72f8e18e8b539109ab512455fe195", "status": "affected", "versionType": "git" }, { "version": "b2a4df200d570b2c33a57e1ebfa5896e4bc81b69", "lessThan": "50bb3435a5e627bfbdc52eb4536f49f88b3486b8", "status": "affected", "versionType": "git" }, { "version": "b2a4df200d570b2c33a57e1ebfa5896e4bc81b69", "lessThan": "66288dcadf80974436250e9f70ed848836b835b5", "status": "affected", "versionType": "git" }, { "version": "b2a4df200d570b2c33a57e1ebfa5896e4bc81b69", "lessThan": "43a1e3744548e6fd85873e6fb43e293eb4010694", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "security/keys/keyring.c" ], "versions": [ { "version": "3.13", "status": "affected" }, { "version": "0", "lessThan": "3.13", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.175", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.142", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.92", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.34", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0.11", "lessThanOrEqual": "7.0.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.13", "versionEndExcluding": "6.1.175" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.13", "versionEndExcluding": "6.6.142" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.13", "versionEndExcluding": "6.12.92" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.13", "versionEndExcluding": "6.18.34" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.13", "versionEndExcluding": "7.0.11" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.13", "versionEndExcluding": "7.1" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/4c5d407ba3ff7f30561ff73ba1b07ed70c864edc" }, { "url": "https://git.kernel.org/stable/c/cefa4265b11176c897a7d9e8e54d89e3701c5584" }, { "url": "https://git.kernel.org/stable/c/5659e6923cb72f8e18e8b539109ab512455fe195" }, { "url": "https://git.kernel.org/stable/c/50bb3435a5e627bfbdc52eb4536f49f88b3486b8" }, { "url": "https://git.kernel.org/stable/c/66288dcadf80974436250e9f70ed848836b835b5" }, { "url": "https://git.kernel.org/stable/c/43a1e3744548e6fd85873e6fb43e293eb4010694" } ], "title": "security/keys: fix missed RCU read section on lookup", "x_generator": { "engine": "bippy-1.2.0" } } } }