CVE-2026-23273: Linux kernel · Race Condition
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 7.8 High · fixed in e3f000f0dee1bfab52e2e61ca6a3835d9e187e35 : patch Linux kernel soon.
Data as of 26 Oct 2026, 13:47 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 e3f000f0dee1bfab52e2e61ca6a3835d9e187e35, d34f7a8aa9a25b7e64e0e46e444697c0f702374d, a1f686d273d129b45712d95f4095843b864466bd +11
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 20 Mar 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 to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in– |
AI-suggested
A fix is available and has been applied in Linux kernel versions 6.18.14, 6.12.75, 6.6.128, 6.1.165, and others as listed. Users and administrators should upgrade to these fixed versions or later to mitigate this vulnerability. No additional mitigations are indicated by the vendor advisory.
Description
CVE-2026-23273 is a race condition vulnerability in the Linux kernel's macvlan network driver. The flaw occurs in the macvlan_common_newlink() function where a device may be made visible before error detection completes, leading to a use-after-free condition. This can cause kernel memory corruption and potentially allow an attacker with local privileges to cause denial of service or escalate privileges. The issue has been fixed in multiple Linux kernel versions.
References
- git.kernel.org/stable/c/91e4ff8d966978901630fc29582c1a76d3c6e46c (opens in a new tab)
- git.kernel.org/stable/c/3d94323c80d7fc4da5f10f9bb06a45d39d5d3cc4 (opens in a new tab)
- git.kernel.org/stable/c/721eb342d9ba19bad5c4815ea3921465158b7362 (opens in a new tab)
- git.kernel.org/stable/c/19c7d8ac51988d053709c1e85bd8482076af845d (opens in a new tab)
- git.kernel.org/stable/c/a1f686d273d129b45712d95f4095843b864466bd (opens in a new tab)
- git.kernel.org/stable/c/d34f7a8aa9a25b7e64e0e46e444697c0f702374d (opens in a new tab)
- git.kernel.org/stable/c/1e58ae87ad1e6e24368dea9aec9048c758cd0e2b (opens in a new tab)
- git.kernel.org/stable/c/e3f000f0dee1bfab52e2e61ca6a3835d9e187e35 (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-082556.html (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-019113.html (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-457936.html (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-784472.html (opens in a new tab)