CVE-2026-80561: libceph: fix multiple unsafe decodes in decode_locker()

highCVSS 7.1CVE-2026-80561

CSIRTS triage

vendor: Linux product: Linux kernel Code injection Memory corruption

What: libceph decode_locker() function performs multiple unsafe decodes without proper bounds checking, risking memory corruption.
Who is affected: Systems using Ceph distributed storage with the affected libceph version.
Urgency: High severity (CVSS 7.1) with no known active exploitation; patch promptly.
Action: Apply the kernel patch that fixes unsafe decodes in decode_locker().

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: high — CVSS 7.1
Published: 2026-08-11
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-80561

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-805610.52% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 42% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-80561	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

criticalCVE-2026-80561: In the Linux kernel, the following vulnerability has been resolved: libceph: fix multiple unsa…nvd

Recent advisories for libceph

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

criticalCVE-2026-80561: In the Linux kernel, the following vulnerability has been resolved: libceph: fix multiple unsa…nvd · 2026-08-26
criticalCVE-2026-80558: In the Linux kernel, the following vulnerability has been resolved: libceph: Avoid using inval…nvd · 2026-08-26
criticalCVE-2026-80557: In the Linux kernel, the following vulnerability has been resolved: libceph: fix OOB read in d…nvd · 2026-08-26
highCVE-2026-68433: In the Linux kernel, the following vulnerability has been resolved: libceph: bound get_version…nvd · 2026-08-12
mediumCVE-2026-68157: libceph: guard missing CRUSH type name lookupmsrc · 2026-08-11
mediumCVE-2026-68154: libceph: reject zero bucket types in crush_decodemsrc · 2026-08-11