CVE-2026-97958: Linux kernel · net/sched: cls_api: Don't replay RTM_GETCHAIN in tc_ctl_chain().
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 26 Oct 2026, 14:05 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 7% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Exploitation evidence
Disclosed: evidence found.
CVE published 25 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 restrict replay logic to RTM_NEWCHAIN requests only, preventing CPU hogging from repeated RTM_GETCHAIN requests. Users should apply the official kernel updates that include this fix. Patch status is not explicitly stated in the input data, so verify with the vendor or distribution advisory for the exact patched versions and update accordingly.
Description
A vulnerability in the Linux kernel's net/sched cls_api subsystem was resolved to prevent excessive CPU usage and system hangs caused by repeated RTM_GETCHAIN requests on netlink sockets without reading responses. The issue arises when tc_ctl_chain() replays RTM_GETCHAIN requests unnecessarily, leading to CPU hogging and a hung task state. The fix restricts replay logic to RTM_NEWCHAIN requests only. This vulnerability affects specific versions of the linux-hwe-edge kernel.
References
- ubuntu.com/security/CVE-2026-97958 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-97958 (opens in a new tab)
- git.kernel.org/stable/c/e9ac395bb56122a057d0aa91a6b55d9e3fa37c26 (opens in a new tab)
- git.kernel.org/stable/c/dff39930ad5e53d202bfdfb14687d1d2fd753b4d (opens in a new tab)
- git.kernel.org/stable/c/503ba58481e3ba69d28127d35a39cec529f9670c (opens in a new tab)
- git.kernel.org/stable/c/a1c2840d95af1fa3d83ba71e23fa0c674a4c6796 (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-97958 (opens in a new tab)
- git.kernel.org/stable/c/240251a4ca7cda213103694b6e21c4a5745e5d8b (opens in a new tab)
- git.kernel.org/stable/c/6558b0d46c5941ed1aa67da8878e224c54239cc5 (opens in a new tab)
- git.kernel.org/stable/c/96c2fc5daf983af2e0c1256c31e89c1f3f855279 (opens in a new tab)
- git.kernel.org/stable/c/9a0f07f7dbd1bfe8c2fd03ad055e9e60a703d5df (opens in a new tab)