CVE-2026-46173: linux Out-of-bounds Write
Vulnerability summary
CVE-2026-46173 is a high (CVSS 7.8) Out-of-bounds Write vulnerability in linux. EPSS estimates a 0.18% chance of exploitation in the next 30 days, higher than 7% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 198 · Related 191Showing 100 of 198. Use Open JSON for the complete list.
Timeline
- 28-05-2026PublishedVulnerability first disclosed.
- 19-10-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: exit: prevent preemption of oopsing TASK_DEAD task When an already-exiting task oopses, make_task_dead() currently calls do_task_dead() with preemption enabled. That is forbidden: do_task_dead() calls __schedule(), which has a comment saying "WARNING: must be called with preemption disabled!". If an oopsing task is preempted in do_task_dead(), between becoming TASK_DEAD and entering the scheduler explicitly, bad things happen: finish_task_switch() assumes that once the scheduler has switched away from a TASK_DEAD task, the task can never run again and its stack is no longer needed; but that assumption apparently doesn't hold if the dead task was preempted (the SM_PREEMPT case). This means that the scheduler ends up repeatedly dropping references on the dead task's stack, which can lead to use-after-free or double-free of the entire task stack; in other words, two tasks can end up running on the same stack, resulting in various kinds of memory corruption. (This does not just affect "recursively oopsing" tasks; it is enough to oops once during task exit, for example in a file_operations::release handler)
CVSS metrics
4 scores · 4 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- NVDNIST7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.18%
Chance of exploitation in the next 30 days
Percentile
7%
Versus all other CVEs
30-day change
+0.05 pp
From 0.13% on 19-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.
- CWE-416Use After FreeThe product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.
Affected systems
Ubuntu139 products
- linux< 6.8.0-136.136 | All versions (No fix recorded) | < 7.0.0-28.28
- linux-allwinner-5.19All versions (No fix recorded)
- linux-aws< 6.8.0-1061.64 | All versions (No fix recorded) | < 7.0.0-1009.9
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ 7f80a2fd7db9a55894fd841915236aca611291b5, < 3d6fb8a7690c23e3213c4b008f64d89a44b98737 | ≥ 7f80a2fd7db9a55894fd841915236aca611291b5, < 640b4c00fb0e2920327435f6176cbefc3c546165 | ≥ 7f80a2fd7db9a55894fd841915236aca611291b5, < 7b2800ba5f5f77a8ee7f4cbadb19cf1264597a34 | ≥ 7f80a2fd7db9a55894fd841915236aca611291b5, < 6f49f94f3b11fe8bff1bf2a054143789e76aaf17 | ≥ 7f80a2fd7db9a55894fd841915236aca611291b5, < 9756b3db5db6c2f5eccb32dddbd88eb4c54f575e | ≥ 7f80a2fd7db9a55894fd841915236aca611291b5, < c1fa0bb633e4a6b11e83ffc57fa5abe8ebb87891 | 5.17
- linux_kernel≥ 5.17, < 6.1.175 | ≥ 6.2, < 6.6.140 | ≥ 6.7, < 6.12.88 | ≥ 6.13, < 6.18.30 | ≥ 6.19, < 7.0.7 | 7.1:rc1 | 7.1:rc2 | 7.1:rc3
Debian1 product
- linux< 6.1.176-1 | < 6.12.88-1 | < 7.0.7-1
3 vendors · 142 products