critical 9.1

CVE-2025-71183 in the critical feed json

btrfs: always detect conflicting inodes when logging inode refs

published 2026-01-31 9 mo ago modified 2026-10-19 20 d ago also EUVD-2025-206592

cvss: 9.1; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 24%
public exploits: 0; none known

In the Linux kernel, the following vulnerability has been resolved:

After rename exchanging (either with the rename exchange operation or regular renames in multiple non-atomic steps) two inodes and at least one of them is a directory, we can end up with a log tree that contains only of the inodes and after a power failure that can result in an attempt to delete the other inode when it should not because it was not deleted before the power failure. In some case that delete attempt fails when the target inode is a directory that contains a subvolume inside it, since the log replay code is not prepared to deal with directory entries that point to root items (only inode items).

1) We have directories "dir1" (inode A) and "dir2" (inode B) under the same parent directory;

2) We have a file (inode C) under directory "dir1" (inode A);

3) We have a subvolume inside directory "dir2" (inode B);

4) All these inodes were persisted in a past transaction and we are currently at transaction N;

5) We rename the file (inode C), so at btrfs_log_new_name() we update inode C's last_unlink_trans to N;

6) We get a rename exchange for "dir1" (inode A) and "dir2" (inode B), so after the exchange "dir1" is inode B and "dir2" is inode A. During the rename exchange we call btrfs_log_new_name() for inodes A and B, but because they are directories, we don't update their last_unlink_trans to N;

7) An fsync against the file (inode C) is done, and because its inode has a last_unlink_trans with a value of N we log its parent directory (inode A) (through btrfs_log_all_parents(), called from btrfs_log_inode_parent()).

8) So we end up with inode B not logged, which now has the old name of inode A. At copy_inode_items_to_log(), when logging inode A, we did not check if we had any conflicting inode to log because inode A has a generation lower than the current transaction (created in a past transaction);

9) After a power failure, when replaying the log tree, since we find that inode A has a new name that conflicts with the name of inode B in the fs tree, we attempt to delete inode B... this is wrong since that directory was never deleted before the power failure, and because there is a subvolume inside that directory, attempting to delete it will fail since replay_dir_deletes() and btrfs_unlink_inode() are not prepared to deal with dir items that point to roots instead of inodes.

When that happens the mount fails and we get a stack trace like the following:

[87.2314] BTRFS info (device dm-0): start tree-log replay [87.2318] BTRFS critical (device dm-0): failed to delete reference to subvol, root 5 inode 256 parent 259 [87.2332] ------------[ cut here ]------------ [87.2338] BTRFS: Transaction aborted (error -2) [87.2346] WARNING: CPU: 1 PID: 638968 at fs/btrfs/inode.c:4345 __btrfs_unlink_inode+0x416/0x440 [btrfs] [87.2368] Modules linked in: btrfs loop dm_thin_pool (...) [87.2470] CPU: 1 UID: 0 PID: 638968 Comm: mount Tainted: G W 6.18.0-rc7-btrfs-next-218+ #2 PREEMPT(full) [87.2489] Tainted: [W]=WARN [87.2494] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014 [87.2514] RIP: 0010:__btrfs_unlink_inode+0x416/0x440 [btrfs] [87.2538] Code: c0 89 04 24 (...) [87.2568] RSP: 0018:ffffc0e741f4b9b8 EFLAGS: 00010286 [87.2574] RAX: 0000000000000000 RBX: ffff9d3ec8a6cf60 RCX: 0000000000000000 [87.2582] RDX: 0000000000000002 RSI: ffffffff84ab45a1 RDI: 00000000ffffffff [87.2591] RBP: ffff9d3ec8a6ef20 R08: 0000000000000000 R09: ffffc0e741f4b840 [87.2599] R10: ffff9d45dc1fffa8 R11: 0000000000000003 R12: ffff9d3ee26d77e0 [87.2608] R13: ffffc0e741f4ba98 R14: ffff9d4458040800 R15: ffff9d44b6b7ca10 [87.2618] FS: 00007f7b9603a840(0000) GS:ffff9d4658982000(0000) knlGS:0000000000000000 [87. ---truncated---

Patch / fix

fixed in 1 distros 4 links 5

Linux Linux 3.19, 4.2, 4.5, 4.6, 6.1.161, 6.6.121, 6.12.66, 6.18.6, 6.19

debian ubuntu suse opensuse

linux Debian 12 6.1.162-1
linux Debian 13 6.12.69-1
linux Debian 14 6.18.8-1

debian advisories DEBIAN-CVE-2025-71183

linux Ubuntu 24.04 LTS 6.8.0-117.117
linux-aws Ubuntu 24.04 LTS 6.8.0-1055.58
linux-gcp Ubuntu 24.04 LTS 6.8.0-1058.61
linux-gke Ubuntu 24.04 LTS 6.8.0-1054.60
linux-ibm Ubuntu 24.04 LTS 6.8.0-1055.56
linux-azure Ubuntu 24.04 LTS 6.8.0-1056.62
linux-gkeop Ubuntu 24.04 LTS 6.8.0-1041.44
linux-raspi Ubuntu 24.04 LTS 6.8.0-1056.60

ubuntu advisories UBUNTU-CVE-2025-71183

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

kernel-default SLES for SAP 15 SP6, SLES 15 SP6-LTSS, SLE Live Patching 15 SP6 +1 more 6.4.0-150600.23.143.1
kernel-64kb SLE Module for Basesystem 15 SP7 6.4.0-150700.53.55.1
kernel-syms SLE Module for Development Tools 15 SP7 6.4.0-150700.53.55.1
kernel-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.53.55.1
kernel-source SLE Module for Development Tools 15 SP7, SLE Module for Basesystem 15 SP7 6.4.0-150700.53.55.1
kernel-default SLE Workstation Extension 15 SP7, SLE Module for Legacy 15 SP7, SLE Module for Basesystem 15 SP7 +2 more 6.4.0-150700.53.55.1
kernel-zfcpdump SLE Module for Basesystem 15 SP7 6.4.0-150700.53.55.1
kernel-obs-build SLE Module for Development Tools 15 SP7 6.4.0-150700.53.55.1

suse advisories SUSE-SU-2026:4934-1 SUSE-SU-2026:2238-1 SUSE-SU-2026:1078-1 SUSE-SU-2026:20873-1 SUSE-SU-2026:20838-1 SUSE-SU-2026:20931-1

kernel-rt openSUSE Leap 16.0 6.12.0-160000.27.1
dtb-aarch64 openSUSE Leap 16.0 6.12.0-160000.27.1
kernel-64kb openSUSE Leap 16.0 6.12.0-160000.27.1
kernel-syms openSUSE Leap 16.0 6.12.0-160000.27.1
kernel-azure openSUSE Leap 16.0 6.12.0-160000.27.1
kernel-obs-qa openSUSE Leap 16.0 6.12.0-160000.27.1
kernel-source openSUSE Leap 16.0 6.12.0-160000.27.1
kernel-default openSUSE Leap 16.0 6.12.0-160000.27.1

opensuse advisories openSUSE-SU-2026:20416-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2025-71183 updated 2026-11-07 cvss 5.5

kernel: btrfs: always detect conflicting inodes when logging inode refs

Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more
affected: no fix planned “Out of support scope”
Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more
affected: no fix available “Fix deferred”
Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more Red Hat Enterprise Linux 10 kernel
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 24 d ago (2026-10-16)

Exploit prediction

0.32% chance of exploitation in the next 30 days, higher than 24% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	9.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
NVD	3.1	5.5	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected products

Linux Linux

Classification

Weakness

CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization

Technology feeds

Linux kernel rss critical rss

References

Sources

CVE List CVE-2025-71183
NVD CVE-2025-71183

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary