CVE-2026-23223 | xfs: fix UAF in xchk_btree_check_block_owner

In the Linux kernel, the following vulnerability has been resolved: xfs: fix UAF in xchk_btree_check_block_owner We cannot dereference bs->cur when trying to determine if bs->cur aliases bs->sc->sa.{bno,rmap}_cur after the latter has been freed. Fix this by sampling before type before any freeing could happen. The correct temporal ordering was broken when we removed xfs_btnum_t.

Published: 2026-02-18 Last update: 2026-03-18 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Conclusion & alert: CVE-2026-23223 is rated Low Risk (32.5/100): CVSS High severity, with low exploitation likelihood (EPSS 0.02%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-23223

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-02-19 0.02%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-23223

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.8 5.9 [email protected]

Weakness enumeration for CVE-2026-23223

OS Trackers for CVE-2026-23223

vendor priority summary link
debian unimportant CVE-2026-23223 unimportant priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2026-23223
redhat medium https://access.redhat.com/security/cve/CVE-2026-23223
suse medium CVE-2026-23223 severity moderate: SUSE including 132 source package names (2.2.1-5.81:libblkid1-2.40.4-slfo.1.1_4.1, 2.2.1-5.81:libfdisk1-2.40.4-slfo.1.1_4.1, …), 293 product×package rows across 23 product lines (Container suse/sl-micro/6.1/baremetal-os-container, Container suse/sl-micro/6.1/base-os-container, … (23 product lines)): Fixed 231, Known Not Affected 37, First Fixed 25. https://www.suse.com/security/cve/CVE-2026-23223/
ubuntu medium CVE-2026-23223 medium priority: Ubuntu including 157 source packages (linux, linux-allwinner-5.19, …), 1256 status rows across 8 suites (bionic, focal, jammy, noble, questing, trusty, upstream, xenial): DNE 871, ignored 169, not-affected 112, released 83, needed 21. https://ubuntu.com/security/CVE-2026-23223

Affected software / configurations for CVE-2026-23223

Vendor Product Version Raw CPE
linux linux_kernel >= 6.9, < 6.12.72 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.13, < 6.18.11 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.19, < 6.19.1 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

References for CVE-2026-23223

cvelogic Threat Intelligence