CVE-2026-64187

Published Jul 20, 2026

Last updated 2 months ago

CVSS medium 5.5

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: xfs: fail recovery on a committed log item with no regions If the first op of a transaction is a bare transaction header (len == sizeof(struct xfs_trans_header)), xlog_recover_add_to_trans() adds an item but no region, leaving it on r_itemq with ri_cnt == 0 and ri_buf == NULL. The header can be split across op records, so later ops may still add regions; the item is only invalid if the transaction commits with none. The runtime commit path never emits such a transaction, so this only happens on a crafted log. It came from an AI-assisted code audit of the recovery parser. xlog_recover_reorder_trans() calls ITEM_TYPE() on the item, which reads *(unsigned short *)item->ri_buf[0].iov_base and faults on the NULL ri_buf. Reject it there, before the commit handlers that also read ri_buf[0]. KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:xlog_recover_reorder_trans (fs/xfs/xfs_log_recover.c:1836) xlog_recover_commit_trans (fs/xfs/xfs_log_recover.c:2043) xlog_recover_process_data (fs/xfs/xfs_log_recover.c:2501) xlog_do_recovery_pass (fs/xfs/xfs_log_recover.c:3244) xlog_recover (fs/xfs/xfs_log_recover.c:3493) xfs_log_mount (fs/xfs/xfs_log.c:618) xfs_mountfs (fs/xfs/xfs_mount.c:1034) xfs_fs_fill_super (fs/xfs/xfs_super.c:1938) vfs_get_tree (fs/super.c:1695) path_mount (fs/namespace.c:4161) __x64_sys_mount (fs/namespace.c:4367)
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

nvd@nist.gov
CWE-476

Social media

Hype score
Not currently trending

  1. 🚨 Linux kernel patched 400+ vulnerabilities in ~24 hours (July 19-20). Key CVEs to know: 🔹 CVE-2026-64187 – XFS recovery failure 🔹 CVE-2026-64206 – Bluetooth L2CAP locking issue 🔹 CVE-2026-64192 – BPF inode-storage map flaw 🔹 CVE-2026-64188 – UAF in Qual

    @techepages

    21 Jul 2026

    48 Impressions

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  2. 🚨 New Linux kernel CVEs disclosed (July 19-20): deadlocks, livelocks & NULL pointer crashes across XFS, Bluetooth L2CAP, netfilter, and networking subsystems. Standouts: 🔹 CVE-2026-64206: Bluetooth teardown deadlock 🔹 CVE-2026-64187: XFS log recovery corruption

    @techepages

    21 Jul 2026

    62 Impressions

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Configurations

Related CVEs

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References

Sources include official advisories and independent security research.