CVE-2026-43053 | xfs: close crash window in attr dabtree inactivation

In the Linux kernel, the following vulnerability has been resolved: xfs: close crash window in attr dabtree inactivation When inactivating an inode with node-format extended attributes, xfs_attr3_node_inactive() invalidates all child leaf/node blocks via xfs_trans_binval(), but intentionally does not remove the corresponding entries from their parent node blocks. The implicit assumption is that xfs_attr_inactive() will truncate the entire attr fork to zero extents afterwards, so log recovery will never reach the root node and follow those stale pointers. However, if a log shutdown occurs after the leaf/node block cancellations commit but before the attr bmap truncation commits, this assumption breaks. Recovery replays the attr bmap intact (the inode still has attr fork extents), but suppresses replay of all cancelled leaf/node blocks, maybe leaving them as stale data on disk. On the next mount, xlog_recover_process_iunlinks() retries inactivation and attempts to read the root node via the attr bmap. If the root node was not replayed, reading the unreplayed root block triggers a metadata verification failure immediately; if it was replayed, following its child pointers to unreplayed child blocks triggers the same failure: XFS (pmem0): Metadata corruption detected at xfs_da3_node_read_verify+0x53/0x220, xfs_da3_node block 0x78 XFS (pmem0): Unmount and run xfs_repair XFS (pmem0): First 128 bytes of corrupted metadata buffer: 00000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000050: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ XFS (pmem0): metadata I/O error in "xfs_da_read_buf+0x104/0x190" at daddr 0x78 len 8 error 117 Fix this in two places: In xfs_attr3_node_inactive(), after calling xfs_trans_binval() on a child block, immediately remove the entry that references it from the parent node in the same transaction. This eliminates the window where the parent holds a pointer to a cancelled block. Once all children are removed, the now-empty root node is converted to a leaf block within the same transaction. This node-to-leaf conversion is necessary for crash safety. If the system shutdown after the empty node is written to the log but before the second-phase bmap truncation commits, log recovery will attempt to verify the root block on disk. xfs_da3_node_verify() does not permit a node block with count == 0; such a block will fail verification and trigger a metadata corruption shutdown. on the other hand, leaf blocks are allowed to have this transient state. In xfs_attr_inactive(), split the attr fork truncation into two explicit phases. First, truncate all extents beyond the root block (the child extents whose parent references have already been removed above). Second, invalidate the root block and truncate the attr bmap to zero in a single transaction. The two operations in the second phase must be atomic: as long as the attr bmap has any non-zero length, recovery can follow it to the root block, so the root block invalidation must commit together with the bmap-to-zero truncation.

Published: 2026-05-01 Last update: 2026-05-07 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-43053 is rated Low Risk (20.6/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.02%). 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-2026-43053

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 2026-05-02 — 0.02% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-43053

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.7 3.1 MEDIUM
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/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:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
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:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.0 3.6 [email protected]

Weakness enumeration for CVE-2026-43053

GitHub Security Advisory for CVE-2026-43053

GHSA-37p6-c4xv-cq5q · Severity: medium — In the Linux kernel, the following vulnerability has been resolved: xfs: close crash window in...

OS Trackers for CVE-2026-43053

vendor priority summary link
debian not yet assigned CVE-2026-43053 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 3, resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-43053
redhat medium — https://access.redhat.com/security/cve/CVE-2026-43053
suse medium CVE-2026-43053 severity moderate: SUSE including 14 source package names (cluster-md-kmp-default, dlm-kmp-default, …), 53 product×package rows across 12 product lines (SUSE Linux Enterprise Live Patching 12 SP5, SUSE Linux Enterprise Micro 5.0, … (12 product lines)): Known Not Affected 53. https://www.suse.com/security/cve/CVE-2026-43053/
ubuntu medium CVE-2026-43053 medium priority: Ubuntu including 161 source packages (linux, linux-allwinner-5.19, …), 1449 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): DNE 1048, ignored 173, needed 130, released 83, not-affected 10, needs-triage 5. https://ubuntu.com/security/CVE-2026-43053

Affected software / configurations for CVE-2026-43053

Vendor Product Version Raw CPE
linux linux_kernel >= 2.6.12.1, < 6.19.12 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel 2.6.12 cpe:2.3:o:linux:linux_kernel:2.6.12:-:*:*:*:*:*:*
linux linux_kernel 2.6.12 cpe:2.3:o:linux:linux_kernel:2.6.12:rc2:*:*:*:*:*:*
linux linux_kernel 2.6.12 cpe:2.3:o:linux:linux_kernel:2.6.12:rc3:*:*:*:*:*:*
linux linux_kernel 2.6.12 cpe:2.3:o:linux:linux_kernel:2.6.12:rc4:*:*:*:*:*:*
linux linux_kernel 2.6.12 cpe:2.3:o:linux:linux_kernel:2.6.12:rc5:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*

References for CVE-2026-43053

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