CVE-2026-23223
published 2026-02-18CVE-2026-23223: 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…
PriorityP336high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.12%
2.2th percentile
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.
Affected
12 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.18.12-1 (forky) | linux 6.18.12-1 (forky) |
| linux | linux | — | — |
| linux | linux | >= ec793e690f801d97a7ae2a0d429fea1fee4d44aa < 1d411278dda293a507cb794db7d9ed3511c685c6 | 1d411278dda293a507cb794db7d9ed3511c685c6 |
| linux | linux | >= ec793e690f801d97a7ae2a0d429fea1fee4d44aa < ed82e7949f5cac3058f4100f3cd670531d41a266 | ed82e7949f5cac3058f4100f3cd670531d41a266 |
| linux | linux | >= ec793e690f801d97a7ae2a0d429fea1fee4d44aa < ba5264610423d9653aa36920520902d83841bcfd | ba5264610423d9653aa36920520902d83841bcfd |
| linux | linux | >= ec793e690f801d97a7ae2a0d429fea1fee4d44aa < 1c253e11225bc5167217897885b85093e17c2217 | 1c253e11225bc5167217897885b85093e17c2217 |
| linux | linux_kernel | >= 0 < 6.12.73-1 | 6.12.73-1 |
| linux | linux_kernel | >= 0 < 6.18.12-1 | 6.18.12-1 |
| linux | linux_kernel | >= 6.13 < 6.18.11 | 6.18.11 |
| linux | linux_kernel | >= 6.19 < 6.19.1 | 6.19.1 |
| linux | linux_kernel | >= 6.9 < 6.12.72 | 6.12.72 |
| msrc | azl3_kernel_6.6.121.1-1_on_azure_linux_3.0 | — | — |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8LOW
vendor_redhat7.8HIGH
vendor_msrc6.7MEDIUM
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OSV
CVE-2026-23223: 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 tr
osv·2026-02-18·CVSS 7.8
CVE-2026-23223 [HIGH] CVE-2026-23223: 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 tr
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.
GHSA
GHSA-h437-rr98-fx56: 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
ghsa_unreviewed·2026-02-18
CVE-2026-23223 [HIGH] CWE-416 GHSA-h437-rr98-fx56: 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
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.
Red Hat
kernel: xfs: fix UAF in xchk_btree_check_block_owner
vendor_redhat·2026-02-18·CVSS 7.8
CVE-2026-23223 [HIGH] CWE-366 kernel: xfs: fix UAF in xchk_btree_check_block_owner
kernel: 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.
A use-after-free flaw was found in the Linux kernel's XFS filesystem scrub functionality. In xchk_btree_check_block_owner(), the code dereferences bs->cur to check if it aliases with bs->sc->sa.bno_cur or bs->sc->sa.rmap_cur after these cursors may have already been freed. This incorrect temporal ordering was introduced when the xfs_btnum_t type was removed, po
Microsoft
xfs: fix UAF in xchk_btree_check_block_owner
vendor_msrc·2026-02-10·CVSS 6.7
CVE-2026-23223 [HIGH] xfs: fix UAF in xchk_btree_check_block_owner
xfs: fix UAF in xchk_btree_check_block_owner
Mariner: Mariner
Linux: Linux
Customer Action Required: Yes
Remediation: CBL-Mariner Releases
Reference: https://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade
Debian
CVE-2026-23223: linux - In the Linux kernel, the following vulnerability has been resolved: xfs: fix UA...
vendor_debian·2026·CVSS 7.8
CVE-2026-23223 [HIGH] CVE-2026-23223: linux - In the Linux kernel, the following vulnerability has been resolved: xfs: fix UA...
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.
Scope: local
bookworm: resolved
bullseye: resolved
forky: resolved (fixed in 6.18.12-1)
sid: resolved (fixed in 6.18.12-1)
trixie: resolved (fixed in 6.12.73-1)
No detection rules found.
No public exploits indexed.
Wiz
CVE-2026-23223 Impact, Exploitability, and Mitigation Steps | Wiz
blogs_wiz·CVSS 7.8
CVE-2026-23223 [HIGH] CVE-2026-23223 Impact, Exploitability, and Mitigation Steps | Wiz
## CVE-2026-23223 :
Linux Kernel vulnerability analysis and mitigation
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.
Source : NVD
## 7.8
Score
Published February 18, 2026
Severity HIGH
CNA Score N/A
Affected Technologies
Linux Kernel
Linux Debian
Has Public Exploit No
Has CISA KEV Exploit No
CISA KEV Release Date N/A
CISA KEV Due Date N/A
Exploitation Probability Percentile (EPSS) 3.3
Exploitation Probability (EPSS) N/A
Affected packages
Bugzilla
CVE-2026-23223 kernel: xfs: fix UAF in xchk_btree_check_block_owner
bugzilla·2026-02-18·CVSS 7.8
CVE-2026-23223 [HIGH] CVE-2026-23223 kernel: xfs: fix UAF in xchk_btree_check_block_owner
CVE-2026-23223 kernel: 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.
Discussion:
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026021806-CVE-2026-23223-e3d3@gregkh/T
2026-02-18
Published