CVE-2026-43266: Linux kernel · EFI/CPER: don't go past the ARM processor CPER record buffer
Affects Linux kernelSource CVE Database V5
Not known to be exploited · fixed in eae21beecb95a3b69ee5c38a659f774e171d730e : update Linux kernel when convenient.
Data as of 6 Nov 2026, 15:49 UTC
Rated by Threat Radar · No CVSS score from NVD or the CNA
Thin evidence
One scorer or none- 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
- Limited control over the software or limited information exposure
CISA SSVC assessment, 2026-11-06.
- Patch
- Available – fixed in eae21beecb95a3b69ee5c38a659f774e171d730e, ca2aad8771aa9091bc9e42e7d546bd40b72ddcd4, c80113dcfc807308f5ab33847fae77e07531aeb8 +5
Exploitation evidence
Disclosed: evidence found.
CVE published 6 May 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 6 Nov 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| 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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Description
In the Linux kernel, the following vulnerability has been resolved: EFI/CPER: don't go past the ARM processor CPER record buffer There's a logic inside GHES/CPER to detect if the section_length is too small, but it doesn't detect if it is too big. Currently, if the firmware receives an ARM processor CPER record stating that a section length is big, kernel will blindly trust section_length, producing a very long dump. For instance, a 67 bytes record with ERR_INFO_NUM set 46198 and section length set to 854918320 would dump a lot of data going a way past the firmware memory-mapped area. Fix it by adding a logic to prevent it to go past the buffer if ERR_INFO_NUM is too big, making it report instead: [Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 1 [Hardware Error]: event severity: recoverable [Hardware Error]: Error 0, type: recoverable [Hardware Error]: section_type: ARM processor error [Hardware Error]: MIDR: 0xff304b2f8476870a [Hardware Error]: section length: 854918320, CPER size: 67 [Hardware Error]: section length is too big [Hardware Error]: firmware-generated error record is incorrect [Hardware Error]: ERR_INFO_NUM is 46198 [ rjw: Subject and changelog tweaks ]
References
- git.kernel.org/stable/c/c80113dcfc807308f5ab33847fae77e07531aeb8 (opens in a new tab)
- git.kernel.org/stable/c/ca2aad8771aa9091bc9e42e7d546bd40b72ddcd4 (opens in a new tab)
- git.kernel.org/stable/c/a68d22902a6916e10ee235fee609239004e129d0 (opens in a new tab)
- git.kernel.org/stable/c/64eb63f573f497553e1a0c388bbcdd639e0f0704 (opens in a new tab)
- git.kernel.org/stable/c/be10c1bdf64a39832998f54900aa309b3917abcf (opens in a new tab)
- git.kernel.org/stable/c/25b290624b0e3d2f0f90238709ee0b6009b9fde8 (opens in a new tab)
- git.kernel.org/stable/c/45766863baf899059e75595dd3cb1116467f2095 (opens in a new tab)
- git.kernel.org/stable/c/eae21beecb95a3b69ee5c38a659f774e171d730e (opens in a new tab)