Cyber Resilience

CVE-2026-43406

Critical

Published: 08 May 2026

Published
08 May 2026
Modified
21 May 2026
KEV Added
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Patch
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CVSS Score v3.1 9.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
EPSS Score 0.0050 39.2th percentile
Risk Priority 70 floored blend · peak EPSS

Summary

CVE-2026-43406 is a critical-severity Out-of-bounds Read (CWE-125) vulnerability in Linux Linux Kernel. Its CVSS base score is 9.1 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation of Remote Services (T1210); ranked at the 39.2th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

In the Linux kernel, the following vulnerability has been resolved: libceph: prevent potential out-of-bounds reads in process_message_header() If the message frame is (maliciously) corrupted in a way that the length of the control segment ends up being less than the…

more

size of the message header or a different frame is made to look like a message frame, out-of-bounds reads may ensue in process_message_header(). Perform an explicit bounds check before decoding the message header.

CWE(s)
CWE-125

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
attack.mitre.org →
Why these techniques?

OOB read in libceph network message processing enables exploitation of the Ceph remote storage protocol service.

Confidence: MEDIUM · MITRE ATT&CK Enterprise v19.0

Affected Assets

linux
linux kernel
7.0 · 5.11 — 5.15.203 · 5.16 — 6.1.167 · 6.2 — 6.6.130

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References