CVE-2026-80857: Linux kernel · fuse: wait for FR_FINISHED on abort_on_kill to prevent use-after-free
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 26 Oct 2026, 17:16 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 4% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Exploitation evidence
Disclosed: evidence found.
CVE published 4 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix has been implemented in the Linux kernel to address this vulnerability by modifying the abort_on_kill path to wait for the FR_FINISHED event before freeing memory. Users should apply the official kernel updates that include this fix when available.
Description
In the Linux kernel, the following vulnerability has been resolved: fuse: wait for FR_FINISHED on abort_on_kill to prevent use-after-free The abort_on_kill path in request_wait_answer() calls fuse_abort_conn() and returns without waiting for FR_FINISHED. If fuse_dev_do_write() is concurrently processing the same request (FR_LOCKED set), the caller frees req->args while it is still being accessed, causing a use-after-free. Fix this by jumping to the existing wait_event(FR_FINISHED) instead of returning early. The wait will not hang because fuse_abort_conn() ensures all requests are ended.
References
- nvd.nist.gov/vuln/detail/CVE-2026-80857 (opens in a new tab)
- git.kernel.org/stable/c/64b0b5cacbd2fea88001464cb712c9dfc795b26e (opens in a new tab)
- git.kernel.org/stable/c/715cb86e33cda43f5224cdc3fd5610c0b6a46f7a (opens in a new tab)
- ubuntu.com/security/CVE-2026-80857 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-80857 (opens in a new tab)
- git.kernel.org/linus/64b0b5cacbd2fea88001464cb712c9dfc795b26e (opens in a new tab)
- git.kernel.org/stable/c/a8bbb2a60513bf322170903c21462f0bf4f62be2 (opens in a new tab)