CVE-2026-31396: Linux kernel · net: macb: fix use-after-free access to PTP clock
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 7.8 High · fixed in eb652535e9ec795ef5c1078f7578eaaed755268b : patch Linux kernel soon.
Data as of 10 Nov 2026, 13:05 UTC
Thin evidence
One scorer or none| CNA (Linux) | CVSS 3.1 | 7.8 |
|---|
- Patch
- Available – fixed in eb652535e9ec795ef5c1078f7578eaaed755268b, 8820ffe0975fd2efbe50453e9179c8e1c33a13d3, 5653af416a48f6c18f9626ae9df96f814f45ff34 +5
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
Weaponized: 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 10 Nov 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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AI-suggested
A fix for this vulnerability is available and has been incorporated in Linux kernel versions after 4.11. Users and administrators should update to a fixed kernel version that includes the patches referenced by the commit hashes provided. Since this is a kernel-level vulnerability, applying the official kernel updates is the recommended remediation. No additional mitigations are indicated by the vendor advisory.
Description
CVE-2026-31396 is a use-after-free vulnerability in the Linux kernel's macb network driver related to the Precision Time Protocol (PTP) clock. The PTP clock is registered each time the network interface is opened and destroyed when it is closed. However, it can still be accessed via the ethtool get_ts_info call while the interface is present but after the clock has been freed, leading to a use-after-free condition. This flaw can cause kernel memory corruption and potentially allow an attacker with local privileges to compromise system integrity.
References
- git.kernel.org/stable/c/8820ffe0975fd2efbe50453e9179c8e1c33a13d3 (opens in a new tab)
- git.kernel.org/stable/c/6b757f345eeea87ed5d8afd6de35b927a1a57a2f (opens in a new tab)
- git.kernel.org/stable/c/341d01087f821aa0f165fb1ffc8bfe4e50776da7 (opens in a new tab)
- git.kernel.org/stable/c/5653af416a48f6c18f9626ae9df96f814f45ff34 (opens in a new tab)
- git.kernel.org/stable/c/0bb848d8c64938024e45780f8032f1f67d3a3607 (opens in a new tab)
- git.kernel.org/stable/c/1f4714065b2bcbb0a4013fd355b84b848e6cc345 (opens in a new tab)
- git.kernel.org/stable/c/eb652535e9ec795ef5c1078f7578eaaed755268b (opens in a new tab)
- git.kernel.org/stable/c/8da13e6d63c1a97f7302d342c89c4a56a55c7015 (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)