CVE-2026-23214: btrfs: reject new transactions if the fs is fully read-only

highCVSS 8.4CVE-2026-23214

CSIRTS triage

vendor: Linux product: Linux kernel Denial of service

What: A race condition allows new filesystem transactions on fully read-only btrfs filesystems, causing inconsistencies.
Who is affected: Linux systems using btrfs filesystems mounted in read-only mode.
Urgency: High priority; CVSS 8.4 indicates serious impact and read-only filesystems can be compromised.
Action: Apply kernel patch to reject transaction creation when btrfs filesystem is fully read-only.

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

⚡ Watch Linux kernel

Get an email when a new Linux kernel advisory drops — max one per day, one-click unsubscribe.

Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: high — CVSS 8.4
Published: 2026-08-06
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23214

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-2026-232140.11% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 2% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-23214	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

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

high[UPDATE] [high] Linux Kernel: Multiple vulnerabilitiescert-bund

Recent advisories for btrfs

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-2026-74723: In the Linux kernel, the following vulnerability has been resolved: btrfs: lzo: reject inline …nvd · 2026-08-22
unknownCVE-2026-74722: In the Linux kernel, the following vulnerability has been resolved: btrfs: fix memory leak in …nvd · 2026-08-22
highCVE-2026-74572: In the Linux kernel, the following vulnerability has been resolved: btrfs: zoned: fix deadlock…nvd · 2026-08-15
unknownCVE-2026-74571: In the Linux kernel, the following vulnerability has been resolved: btrfs: skip global block r…nvd · 2026-08-15
highCVE-2026-74321: In the Linux kernel, the following vulnerability has been resolved: btrfs: fix invalid pointer…nvd · 2026-08-15
unknownCVE-2026-74319: In the Linux kernel, the following vulnerability has been resolved: btrfs: zoned: fix deadlock…nvd · 2026-08-15