CVE-2026-89543: Linux kernel · sunrpc: fix use-after-free in __rpc_clnt_handle_event and __rpc_clnt_remove_pipedir
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
- 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Exploitation evidence
Disclosed: evidence found.
CVE published 11 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 for this vulnerability has been implemented in the affected Linux kernel versions. Users should apply the official kernel updates that address this issue. Since this is not a cloud service, remediation depends on deploying patched kernel versions. Patch status is not explicitly confirmed in the provided data; users should consult their Linux distribution or vendor advisories for the latest patches.
Description
A use-after-free vulnerability in the Linux kernel's sunrpc subsystem was fixed. The issue involves stale pointers to pipefs superblocks after mount or unmount events, which can lead to use-after-free conditions during certain RPC info calls. This vulnerability affects specific versions of the linux-hwe-edge kernel and has been resolved by properly updating and clearing internal pointers during mount and unmount operations.
References
- nvd.nist.gov/vuln/detail/CVE-2026-89543 (opens in a new tab)
- git.kernel.org/stable/c/932a8cf6abb2b2f8677b79153a823108d8861fe2 (opens in a new tab)
- git.kernel.org/stable/c/cdf7a233cb94774b0e7df42d9157077983f5022c (opens in a new tab)
- git.kernel.org/stable/c/e769fcde3cc73e847b1eb3acd40c04a291cb0c0c (opens in a new tab)
- ubuntu.com/security/CVE-2026-89543 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-89543 (opens in a new tab)
- git.kernel.org/linus/932a8cf6abb2b2f8677b79153a823108d8861fe2 (opens in a new tab)
- git.kernel.org/stable/c/59527bbfb1eabdb28e95e7c725886cc2c2899cb3 (opens in a new tab)
- git.kernel.org/stable/c/f99fedfd1dbffe8d20b421c9a7d4655a135d4fcd (opens in a new tab)