CVE-2026-53245: Linux kernel · net/802/mrp: fix vector attribute parsing in mrp_pdu_parse_vecattr
Affects Linux kernelSource CVE Database V5
Not known to be exploited · fixed in fd9c3a47c670bec6b18f44454cea023f93b5adb3 : update Linux kernel when convenient.
Data as of 6 Nov 2026, 16:49 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 fd9c3a47c670bec6b18f44454cea023f93b5adb3, cc98717e591a963a616fdf15ecf48eefaf45d758, ae65714d96f68bb252eb20085320bdaacab36c00 +5
Exploitation evidence
Disclosed: evidence found.
CVE published 25 Jun 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: net/802/mrp: fix vector attribute parsing in mrp_pdu_parse_vecattr In mrp_pdu_parse_vecattr(), vector attribute events are encoded three per byte and valen tracks the number of events left to process. The parser decrements valen after processing the first and second events from each event byte, but not after processing the third one. When valen is exactly a multiple of three, the loop continues after the last valid event and consumes the next byte as a new event byte, applying a spurious event to the MRP applicant state. Additionally, when valen is zero the parser unconditionally consumes attrlen bytes as FirstValue and advances the offset, even though per IEEE 802.1ak a VectorAttribute with only a LeaveAllEvent has valen of zero and no FirstValue or Vector fields. This corrupts the offset for subsequent PDU parsing. Also, when valen exceeds three the loop crosses byte boundaries but the attribute value is not incremented between the last event of one byte and the first event of the next. This causes the first event of the next byte to use the same attribute value as the third event rather than the next consecutive value. Decrement valen after processing the third event, skip FirstValue consumption when valen is zero, and increment the attribute value at the end of each loop iteration.
References
- git.kernel.org/stable/c/ae65714d96f68bb252eb20085320bdaacab36c00 (opens in a new tab)
- git.kernel.org/stable/c/36d259711872e3b2f6cd76a4d270c21931c0f35f (opens in a new tab)
- git.kernel.org/stable/c/cc98717e591a963a616fdf15ecf48eefaf45d758 (opens in a new tab)
- git.kernel.org/stable/c/6d6e42e8e17f18d61327f8653479c5b5e161ae1d (opens in a new tab)
- git.kernel.org/stable/c/fd9c3a47c670bec6b18f44454cea023f93b5adb3 (opens in a new tab)
- git.kernel.org/stable/c/42446ca0f3570663e87183c065e0b4def52dfba2 (opens in a new tab)
- git.kernel.org/stable/c/6eea6494e542a03cdf755a593b7d74f3f7c260fd (opens in a new tab)
- git.kernel.org/stable/c/7561c7fbc694308da73300f036719e63e42bf0b4 (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-784472.html (opens in a new tab)