CVE-2024-47740
Vulnérabilité élevée dans Linux (Linux)
Description
In the Linux kernel, the following vulnerability has been resolved: f2fs: Require FMODE_WRITE for atomic write ioctls The F2FS ioctls for starting and committing atomic writes check for inode_owner_or_capable(), but this does not give LSMs like SELinux or Landlock an opportunity to deny the write access - if the caller's FSUID matches the inode's UID, inode_owner_or_capable() immediately returns true. There are scenarios where LSMs want to deny a process the ability to write particular files, even files that the FSUID of the process owns; but this can currently partially be bypassed using atomic write ioctls in two ways: - F2FS_IOC_START_ATOMIC_REPLACE + F2FS_IOC_COMMIT_ATOMIC_WRITE can truncate an inode to size 0 - F2FS_IOC_START_ATOMIC_WRITE + F2FS_IOC_ABORT_ATOMIC_WRITE can revert changes another process concurrently made to a file Fix it by requiring FMODE_WRITE for these operations, just like for F2FS_IOC_MOVE_RANGE. Since any legitimate caller should only be using these ioctls when intending to write into the file, that seems unlikely to break anything.
Gravité et risque d'exploitation
CVE-2024-47740 obtient un score CVSS de 7.1/10, soit une gravité élevée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.23 %, ce qui la place devant 13.3 % des CVE référencées.
Que faire ?
- Vérifiez si Linux (versions 6.12, <=6.1.*, <=6.11.*, 6.10.13, 5.4.285, <f3bfac2cabf5333506b263bc0c8497c95302f32d, 0, <4ce87674c3a6b4d3b3d45f85b584ab8618a3cece, <000bab8753ae29a259feb339b99ee759795a48ac, <5e0de753bfe87768ebe6744d869caa92f35e5731, <=5.10.*, <=6.6.*, <32f348ecc149e9ca70a1c424ae8fa9b6919d2713, <88ff021e1fea2d9b40b2d5efd9013c89f7be04ac, <=5.4.*, 6.6.54, <=4.19.*, 6.1.113, <3.18, 4.19.323, <700f3a7c7fa5764c9f24bbf7c78e0b6e479fa653, <=*, <=5.15.*, <4583290898c13c2c2e5eb8773886d153c2c5121d, 88b88a66797159949cec32eaab12b4968f6fae2d, 5.10.227, 5.15.168, <4f5a100f87f32cb65d4bb1ad282a08c92f6f591e, 6.11.2, <=6.10.*, 3.18) 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/700f3a7c7fa5764c9f24bbf7c78e0b6e479fa653
- https://git.kernel.org/stable/c/4ce87674c3a6b4d3b3d45f85b584ab8618a3cece
- https://git.kernel.org/stable/c/000bab8753ae29a259feb339b99ee759795a48ac
- https://git.kernel.org/stable/c/88ff021e1fea2d9b40b2d5efd9013c89f7be04ac
- https://git.kernel.org/stable/c/32f348ecc149e9ca70a1c424ae8fa9b6919d2713
- https://git.kernel.org/stable/c/5e0de753bfe87768ebe6744d869caa92f35e5731
- https://git.kernel.org/stable/c/f3bfac2cabf5333506b263bc0c8497c95302f32d
- https://git.kernel.org/stable/c/4583290898c13c2c2e5eb8773886d153c2c5121d
- https://git.kernel.org/stable/c/4f5a100f87f32cb65d4bb1ad282a08c92f6f591e