CVE-2026-46121
Vulnérabilité non évaluée dans Linux (Linux)
Description
In the Linux kernel, the following vulnerability has been resolved: mm/damon/sysfs-schemes: protect memcg_path kfree() with damon_sysfs_lock Patch series "mm/damon/sysfs-schemes: fix use-after-free for [memcg_]path". Reads of 'memcg_path' and 'path' files in DAMON sysfs interface could race with their writes, results in use-after-free. Fix those. This patch (of 2): damon_sysfs_scheme_filter->mmecg_path can be read and written by users, via DAMON sysfs memcg_path file. It can also be indirectly read, for the parameters {on,off}line committing to DAMON. The reads for parameters committing are protected by damon_sysfs_lock to avoid the sysfs files being destroyed while any of the parameters are being read. But the user-driven direct reads and writes are not protected by any lock, while the write is deallocating the memcg_path-pointing buffer. As a result, the readers could read the already freed buffer (user-after-free). Note that the user-reads don't race when the same open file is used by the writer, due to kernfs's open file locking. Nonetheless, doing the reads and writes with separate open files would be common. Fix it by protecting both the user-direct reads and writes with damon_sysfs_lock.
Gravité et risque d'exploitation
CVE-2026-46121 obtient un score CVSS de 0.0/10, soit une gravité non évaluée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.13 %, ce qui la place devant 2.0 % des CVE référencées.
Que faire ?
- Vérifiez si Linux (versions <=7.0.*, 7.0.7, <=6.12.*, 0, <1e68eb96e8beb1abefd12dd22c5637795d8a877e, 6.12.88, 4f489fe6afb395dbc79840efa3c05440b760d883, <=6.6.*, 6.16, 7.1, <=6.18.*, 6.15.5, 4a158ac0538dd5695eeaa00aa0720d711f3e4ef1, 6.6.96, c5d5b0047b0c0f304608f3824139f7bd34c48413, <6.6.140, <b1e9f2d5870776347edef927f9bb3ea19b8e3abb, <6.16, <=*, <eafd6f5372d29b0dd213799b92c2c9c7ad31d7da, <c88802d0e8edd14b6cd2daf3000f99adbc4c85c5, 6.12.36, 6.6.140, 490a43d07f1663d827e802720d30cbc0494e4f81, <baecc45ad60e621ef14d6c1e7f41ef36bbfdf910, 6.18.30, <6.12.88) 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/b1e9f2d5870776347edef927f9bb3ea19b8e3abb
- https://git.kernel.org/stable/c/c88802d0e8edd14b6cd2daf3000f99adbc4c85c5
- https://git.kernel.org/stable/c/eafd6f5372d29b0dd213799b92c2c9c7ad31d7da
- https://git.kernel.org/stable/c/baecc45ad60e621ef14d6c1e7f41ef36bbfdf910
- https://git.kernel.org/stable/c/1e68eb96e8beb1abefd12dd22c5637795d8a877e