CVE-2026-89784: Linux kernel · SUNRPC: check rpc_sockaddr2uaddr() return value in rpcb_register_inet4/6
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 26 Oct 2026, 12:55 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 11% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Exploitation evidence
Disclosed: evidence found.
CVE published 16 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 is available that adds a NULL check for the return value of rpc_sockaddr2uaddr() in rpcb_register_inet4() and rpcb_register_inet6(), returning -ENOMEM if NULL is encountered. Users should apply the official kernel update that includes this fix. Until patched, systems may experience kernel crashes under memory pressure when using affected RPC services.
Description
A vulnerability in the Linux kernel's SUNRPC subsystem was resolved involving improper handling of a NULL return value from rpc_sockaddr2uaddr() in rpcb_register_inet4() and rpcb_register_inet6(). This can lead to a kernel crash (oops) due to a NULL pointer dereference when the system is under memory pressure. The issue occurs when an in-kernel RPC service registers with the local rpcbind and rpc_sockaddr2uaddr() fails to allocate memory but its return value is unchecked. The fix involves adding a check for NULL and returning an error before the NULL pointer is used.
References
- ubuntu.com/security/CVE-2026-89784 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-89784 (opens in a new tab)
- git.kernel.org/linus/fd22370226a0d8109045d0831fd5aaadee921693 (opens in a new tab)
- git.kernel.org/stable/c/04441b792ec40eb66349b5fab34b6a2090b5b2dd (opens in a new tab)
- git.kernel.org/stable/c/12bf3e0182ccdaf3b412756a756d3944a7dacaa9 (opens in a new tab)
- git.kernel.org/stable/c/4a6095de8cb1858e05bdf70b3e7d6d7645c25041 (opens in a new tab)
- git.kernel.org/stable/c/4e01022974355732e748ec8ebc97c558cb624ffe (opens in a new tab)
- git.kernel.org/stable/c/5a51c49ddb37b883566874aecc66bc5a2e617a96 (opens in a new tab)
- git.kernel.org/stable/c/cda4aacfb0bbf5c0f90fd0b42c72c749635d1368 (opens in a new tab)
- git.kernel.org/stable/c/eb476289c12cc22c8766f8a84eeb7ab46c4e8fb6 (opens in a new tab)
- git.kernel.org/stable/c/fd22370226a0d8109045d0831fd5aaadee921693 (opens in a new tab)