CVE-2026-43365
Vulnérabilité élevée dans Linux (Linux)
Description
In the Linux kernel, the following vulnerability has been resolved: xfs: fix undersized l_iclog_roundoff values If the superblock doesn't list a log stripe unit, we set the incore log roundoff value to 512. This leads to corrupt logs and unmountable filesystems in generic/617 on a disk with 4k physical sectors... XFS (sda1): Mounting V5 Filesystem ff3121ca-26e6-4b77-b742-aaff9a449e1c XFS (sda1): Torn write (CRC failure) detected at log block 0x318e. Truncating head block from 0x3197. XFS (sda1): failed to locate log tail XFS (sda1): log mount/recovery failed: error -74 XFS (sda1): log mount failed XFS (sda1): Mounting V5 Filesystem ff3121ca-26e6-4b77-b742-aaff9a449e1c XFS (sda1): Ending clean mount ...on the current xfsprogs for-next which has a broken mkfs. xfs_info shows this... meta-data=/dev/sda1 isize=512 agcount=4, agsize=644992 blks = sectsz=4096 attr=2, projid32bit=1 = crc=1 finobt=1, sparse=1, rmapbt=1 = reflink=1 bigtime=1 inobtcount=1 nrext64=1 = exchange=1 metadir=1 data = bsize=4096 blocks=2579968, imaxpct=25 = sunit=0 swidth=0 blks naming =version 2 bsize=4096 ascii-ci=0, ftype=1, parent=1 log =internal log bsize=4096 blocks=16384, version=2 = sectsz=4096 sunit=0 blks, lazy-count=1 realtime =none extsz=4096 blocks=0, rtextents=0 = rgcount=0 rgsize=268435456 extents = zoned=0 start=0 reserved=0 ...observe that the log section has sectsz=4096 sunit=0, which means that the roundoff factor is 512, not 4096 as you'd expect. We should fix mkfs not to generate broken filesystems, but anyone can fuzz the ondisk superblock so we should be more cautious. I think the inadequate logic predates commit a6a65fef5ef8d0, but that's clearly going to require a different backport.
Gravité et risque d'exploitation
CVE-2026-43365 obtient un score CVSS de 8.2/10, soit une gravité élevée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.59 %, ce qui la place devant 47.2 % des CVE référencées.
Que faire ?
- Vérifiez si Linux (versions <=6.1.*, <=6.12.*, a6a65fef5ef8d0a6a0ce514eb66b2f3dfa777b48, 6.12.78, 0, 7.0, <5.14, 6.18.19, <=6.6.*, 5.14, <=6.19.*, 5.15.203, <41e91dff2d3974730b5ee50daa8e27ec254cbf91, <2ecda4b83749c1fef0c9dea4fd5e8b513aba3e40, 6.19.9, <=6.18.*, <5e7148402dfc4a5b7894d8e97b15e5c2e70924aa, <52a8a1ba883defbfe3200baa22cf4cd21985d51a, 6.1.167, <e88ce9f0536f3b2149afb70625cfc4bd74a4ac6d, <=*, <446a1f5bb64ba38adb93cb043ff0f7b85e8937ca, <5afae524f83d6a18517298491a5624cb0eae5029, <=5.15.*, 6.6.130) est présent sur votre parc.
- Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
- À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
- Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.
Références
- https://git.kernel.org/stable/c/5afae524f83d6a18517298491a5624cb0eae5029
- https://git.kernel.org/stable/c/2ecda4b83749c1fef0c9dea4fd5e8b513aba3e40
- https://git.kernel.org/stable/c/41e91dff2d3974730b5ee50daa8e27ec254cbf91
- https://git.kernel.org/stable/c/e88ce9f0536f3b2149afb70625cfc4bd74a4ac6d
- https://git.kernel.org/stable/c/446a1f5bb64ba38adb93cb043ff0f7b85e8937ca
- https://git.kernel.org/stable/c/5e7148402dfc4a5b7894d8e97b15e5c2e70924aa
- https://git.kernel.org/stable/c/52a8a1ba883defbfe3200baa22cf4cd21985d51a