CVE-2026-80916kcov: fix data corruption and race conditions on PREEMPT_RT
- —Not scoredno CVSS score yet
- 0.18%Exploitation in 30 daysEPSS · top 92% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: kcov: fix data corruption and race conditions on PREEMPT_RT syzbot is reporting KCOV state corruption on PREEMPT_RT kernels, for the temporary storage used for saving/restoring remote KCOV state is currently allocated as the per-CPU area. On PREEMPT_RT kernels, softirq handlers run as preemptible task threads (e.g., ksoftirqd). If a softirq context preempts a task running a remote KCOV session, it safely saves the task's state into the per-CPU area. However, if that softirq thread is subsequently preempted by a higher- priority softirq thread on the same CPU, the second softirq will overwrite the same per-CPU area, permanently destroying the original task's KCOV state. Fix this data corruption by moving the temporary storage from the per-CPU area to the per-thread area. Since each softirq thread now owns its own task context, nested softirq preemption no longer causes data overwrites. Note that while the temporary storage is now on a per-thread basis, the per-CPU kcov_percpu_data.lock must be retained, for we need to ensure that kcov_remote_start() and kcov_remote_stop() operate atomically without racing against asynchronous interrupts that manipulate the current task's KCOV state. It is likely that GFP_KERNEL allocation by vmalloc_node() in kcov_init() has already called panic() before returning NULL, for there will be no OOM-killable userspace processes when __init function of built-in module runs. But this patch also fixes crashing the kernel when vmalloc_node() in kcov_init() returned NULL, for kcov_init() left per-CPU irq_area == NULL but kcov_remote_start() depends on per-CPU irq_area != NULL, resulting in (1) doing vmalloc() in kcov_remote_start() despite !in_task() context (2) out-of-array-bounds access if (1) succeeded but kcov->remote_size < CONFIG_KCOV_IRQ_AREA_SIZE (3) always leak memory allocated by (1), eventually killing all OOM-killable userspace processes problems.
Timeline
ID reserved
By Linux
- 14 days later
· 14 days later
Published
- 40 days later
· 40 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
No CVSS score yet: neither the CNA, CISA nor NVD has scored this CVE. NVD status: Received.
- EPSS (exploitation in 30 days)
- 0.18% · top 92% of all CVEs (14 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Not scored.
Affected products
- affected 5ff3b30ab57da82d8db4f14662a2858cabfbc2c0 – < ef7048d8a614c5f5a9b20513a5428101a744514e
- affected 5ff3b30ab57da82d8db4f14662a2858cabfbc2c0 – < 8ed3ddf23d39bf5338406bd9f8863d44748cf6ce
- affected 5ff3b30ab57da82d8db4f14662a2858cabfbc2c0 – < 5dc59fc959b2b5742985d7ef24bccd1868217dc2
- affected 5ff3b30ab57da82d8db4f14662a2858cabfbc2c0 – < a2fb8222cde23b0001812ed3acb7c0ea36dd94e2
- affected 5ff3b30ab57da82d8db4f14662a2858cabfbc2c0 – < 18799e858b407bf355383c9dd6c06477aa437134
- affected 5ff3b30ab57da82d8db4f14662a2858cabfbc2c0 – < e11f5b48c82703242a3be7a7ae4b4940b4cb4610
- affected 5ff3b30ab57da82d8db4f14662a2858cabfbc2c0 – < 22670d1552fe155822b2abf91f920925f7d067b4
- affected 5ff3b30ab57da82d8db4f14662a2858cabfbc2c0 – < f8c9a3ec36b4ee3d4701b9be08f40e7bfbf89761
- affected 5ff3b30ab57da82d8db4f14662a2858cabfbc2c0 – < 2eed77fdcb0cc48e8eccb2bcd4b7f2c6d650e84c
- affected 5.8
- unaffected < 5.8
- unaffected 5.10.269 – ≤ 5.10.*
- unaffected 5.15.220 – ≤ 5.15.*
- unaffected 6.1.185 – ≤ 6.1.*
- unaffected 6.6.154 – ≤ 6.6.*
- unaffected 6.12.106 – ≤ 6.12.*
- unaffected 6.18.47 – ≤ 6.18.*
- unaffected 7.1.11 – ≤ 7.1.*
- unaffected 7.2.1 – ≤ 7.2.*
- unaffected 7.3 – ≤ *
References
References9
- https://git.kernel.org/stable/c/ef7048d8a614c5f5a9b20513a5428101a744514e (opens in a new tab)
- https://git.kernel.org/stable/c/8ed3ddf23d39bf5338406bd9f8863d44748cf6ce (opens in a new tab)
- https://git.kernel.org/stable/c/5dc59fc959b2b5742985d7ef24bccd1868217dc2 (opens in a new tab)
- https://git.kernel.org/stable/c/a2fb8222cde23b0001812ed3acb7c0ea36dd94e2 (opens in a new tab)
- https://git.kernel.org/stable/c/18799e858b407bf355383c9dd6c06477aa437134 (opens in a new tab)
- https://git.kernel.org/stable/c/e11f5b48c82703242a3be7a7ae4b4940b4cb4610 (opens in a new tab)
- https://git.kernel.org/stable/c/22670d1552fe155822b2abf91f920925f7d067b4 (opens in a new tab)
- https://git.kernel.org/stable/c/f8c9a3ec36b4ee3d4701b9be08f40e7bfbf89761 (opens in a new tab)
- https://git.kernel.org/stable/c/2eed77fdcb0cc48e8eccb2bcd4b7f2c6d650e84c (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-75091 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-80916)Record last updated .