{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-80622", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-26T14:34:25.775Z", "datePublished": "2026-08-28T06:48:41.744Z", "dateUpdated": "2026-10-16T19:26:30.961Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-29T06:21:27.766Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nchar: tlclk: fix use-after-free in tlclk_cleanup()\n\nThis patch improves the module cleanup process in the tlclk driver to\nprevent potential use-after-free and race conditions.\n\nCurrently, the file_operations structure does not specify the .owner\nfield, which could allow the module to be unloaded while user-space\nprocesses are still interacting with the device. Additionally, the\ntlclk_cleanup() function frees the alarm_events memory before ensuring\nthat blocked processes in the waitqueue are fully awakened and that the\nswitchover_timer has completed.\n\nTo address these cases, this patch:\n- Sets '.owner = THIS_MODULE' in tlclk_fops to safely defer module\n unloading while the device is in use.\n- Updates tlclk_cleanup() to explicitly wake up all blocked readers\n (wake_up_all), properly release hardware I/O regions, and safely\n delete the timer (timer_delete_sync) prior to freeing memory." } ], "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 UAF is reached only via local open/read syscalls on /dev/telco_clock and tlclk_cleanup() during delete_module/rmmod; this x86 ATCA telecom-clock char driver has no network, Bluetooth, or physical-bus attack surface.\nAC:L - Without .owner the attacker controls both sides of the race by keeping /dev/telco_clock open with read() blocked on wq while IRQs remain active, then timing or piggybacking on module unload to hit kfree(alarm_events) against tlclk_read, tlclk_interrupt, or switchover_timeout.\nPR:L - An unprivileged local user with /dev/telco_clock access can open the device and block in read() while IRQs stay registered; per CNA driver-removal UAF precedent, concurrent admin rmmod triggering tlclk_cleanup() does not require the attacker to hold CAP_SYS_MODULE.\nUI:N - No victim interaction is required; the attacker opens /dev/telco_clock and blocks on read() or sustains IRQ/timer activity themselves while module unload occurs during maintenance or coordinated rmmod, without needing another user to act.\nS:U - Kernel heap UAF during tlclk module cleanup affects only the host kernel on the ATCA blade; this is standard in-kernel memory corruption, not a VM escape, IOMMU bypass, or cross-authority sandbox breakout.\nC:H - tlclk_read() performs copy_to_user from freed alarm_events, and tlclk_interrupt/switchover_timeout dereference the freed buffer; this kernel heap UAF enables arbitrary read primitives via controlled slab reuse and information disclosure.\nI:H - tlclk_read() memset() on freed alarm_events and IRQ/timer handlers increment fields in the freed structure, providing kernel heap write primitives exploitable for control-flow hijack via slab spraying and UAF exploitation.\nA:H - Concurrent access to freed alarm_events from read(), switchover_timeout, or tlclk_interrupt during module unload can cause kernel oops/panic; UAF during driver teardown reliably threatens system availability even when not fully weaponized." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/char/tlclk.c" ], "versions": [ { "version": "1a80ba88273097933f93b1f40537337416798c70", "lessThan": "09d8d2a46a9ec9ff728f3159a174a2ab25dd0f0a", "status": "affected", "versionType": "git" }, { "version": "1a80ba88273097933f93b1f40537337416798c70", "lessThan": "96902299a22d126ef5eb3f45cd5d8ceea9e6a735", "status": "affected", "versionType": "git" }, { "version": "1a80ba88273097933f93b1f40537337416798c70", "lessThan": "166dd1d5265e067459e674c11688919901813ec2", "status": "affected", "versionType": "git" }, { "version": "1a80ba88273097933f93b1f40537337416798c70", "lessThan": "764723bd67a6c8f53a8d8309211fb039e2ebcf49", "status": "affected", "versionType": "git" }, { "version": "1a80ba88273097933f93b1f40537337416798c70", "lessThan": "c3f0cd76561ae611c2d247ee96dfd559e4197cb7", "status": "affected", "versionType": "git" }, { "version": "1a80ba88273097933f93b1f40537337416798c70", "lessThan": "3d5e4cc0d9dce79b0429da3134ac7b072ab9009f", "status": "affected", "versionType": "git" }, { "version": "1a80ba88273097933f93b1f40537337416798c70", "lessThan": "42223445607a9a5df3cb1c4729abfe3a5085e7ce", "status": "affected", "versionType": "git" }, { "version": "1a80ba88273097933f93b1f40537337416798c70", "lessThan": "bbf003b7794d6ad6f939fdd29f1f1bde8ac554c1", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/char/tlclk.c" ], "versions": [ { "version": "2.6.15", "status": "affected" }, { "version": "0", "lessThan": "2.6.15", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.261", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.212", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.178", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.145", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.97", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.40", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.5", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "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": "2.6.15", "versionEndExcluding": "5.10.261" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.15", "versionEndExcluding": "5.15.212" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.15", "versionEndExcluding": "6.1.178" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.15", "versionEndExcluding": "6.6.145" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.15", "versionEndExcluding": "6.12.97" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.15", "versionEndExcluding": "6.18.40" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.15", "versionEndExcluding": "7.1.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.15", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/09d8d2a46a9ec9ff728f3159a174a2ab25dd0f0a" }, { "url": "https://git.kernel.org/stable/c/96902299a22d126ef5eb3f45cd5d8ceea9e6a735" }, { "url": "https://git.kernel.org/stable/c/166dd1d5265e067459e674c11688919901813ec2" }, { "url": "https://git.kernel.org/stable/c/764723bd67a6c8f53a8d8309211fb039e2ebcf49" }, { "url": "https://git.kernel.org/stable/c/c3f0cd76561ae611c2d247ee96dfd559e4197cb7" }, { "url": "https://git.kernel.org/stable/c/3d5e4cc0d9dce79b0429da3134ac7b072ab9009f" }, { "url": "https://git.kernel.org/stable/c/42223445607a9a5df3cb1c4729abfe3a5085e7ce" }, { "url": "https://git.kernel.org/stable/c/bbf003b7794d6ad6f939fdd29f1f1bde8ac554c1" } ], "title": "char: tlclk: fix use-after-free in tlclk_cleanup()", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2026-80622", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "total" } ], "version": "2.0.3", "timestamp": "2026-10-16T19:18:55.907096Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-16T19:26:30.961Z" } } ] } }