CVE-2026-23437: Linux kernel · net: shaper: protect late read accesses to the hierarchy
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 7.8 High · fixed in 348758ba74e6a348299965b16a97cfb817545cc0 : patch Linux kernel soon.
Data as of 26 Oct 2026, 17:30 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 2% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Total control over the software or total information disclosure
CISA SSVC assessment, 2026-10-16.
- Patch
- Available – fixed in 348758ba74e6a348299965b16a97cfb817545cc0, 581eee0890a8bde44f1fb78ad3e70502a897d583, 0f9ea7141f365b4f27226898e62220fb98ef8dc6
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 3 Apr 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
Upgrade Linux kernel to 348758ba74e6a348299965b16a97cfb817545cc0, 581eee0890a8bde44f1fb78ad3e70502a897d583 or 0f9ea7141f365b4f27226898e62220fb98ef8dc6.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in– |
AI-suggested
The vulnerability has been fixed in specific Linux kernel commits identified by hashes 348758ba74e6a348299965b16a97cfb817545cc0, 581eee0890a8bde44f1fb78ad3e70502a897d583, and 0f9ea7141f365b4f27226898e62220fb98ef8dc6. Users and administrators should update to a Linux kernel version that includes these fixes. No additional mitigation is required beyond applying the official patch.
Description
CVE-2026-23437 is a high-severity vulnerability in the Linux kernel's network traffic shaper component. It involves improper handling of references to network devices (netdev) during Netlink operations, where a liveness check is missing when converting a reference to a locked netdev. This flaw can lead to unsafe late read accesses to the hierarchy after a netdev might have been unregistered. The issue has been fixed in specific Linux kernel commits.