CVE-2026-68478
Vulnérabilité non évaluée dans Linux (Linux)
Description
In the Linux kernel, the following vulnerability has been resolved: memstick: ms_block: reject a card that reports too many blocks msb_ftl_initialize() computes the zone count from the card block count with no bound: msb->zone_count = msb->block_count / MS_BLOCKS_IN_ZONE; ... for (i = 0; i < msb->zone_count; i++) msb->free_block_count[i] = MS_BLOCKS_IN_ZONE; msb->block_count is a card value. msb_read_boot_blocks() reads number_of_blocks from the card boot page and byte swaps it. free_block_count is a fixed int[MS_MAX_ZONES]. MS_MAX_ZONES is 16, so the valid indices are 0 to 15. The init loop above indexes it by zone_count. msb_mark_block_used() and msb_mark_block_unused() index it by pba / MS_BLOCKS_IN_ZONE, for pba up to block_count - 1. A card may report up to 65535 blocks. A block_count above 8192 (MS_MAX_ZONES * MS_BLOCKS_IN_ZONE) lets the pba index reach 16. That writes past free_block_count[] and corrupts struct msb_data. A larger count runs the init loop past the end too. A real Memory Stick has at most 16 zones. So it has at most 8192 blocks. msb_ftl_initialize() now rejects a card that reports more than MS_MAX_ZONES * MS_BLOCKS_IN_ZONE blocks.
Gravité et risque d'exploitation
CVE-2026-68478 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 0.22 %, ce qui la place devant 11.7 % des CVE référencées.
Que faire ?
- Vérifiez si Linux (versions <8937b11f1c3896e066c3fb07387ba17bc8c50b8a, <=6.1.*, 7.1.5, 6.18.40, <=6.12.*, <a4b9961efe8640f50800811b4a2b2046b3dc2ccc, <b86666ac4009a252501cc17242582a7ec9ed976e, <f1c675ecf6e5ad02722f0019f729d8bb588d502e, 0, 3.12, <=7.1.*, <d5db3439ee8d1c165a09a47e984c4ba508c130df, 6.1.178, <=5.10.*, <=6.6.*, 6.12.97, <=6.18.*, 5.15.212, 6.6.145, 5.10.261, 0ab30494bc4f3bc1ea4659b7c5d97c5218554a63, <39151f0708c84221e94cdd6aa070aba5d7cb1c01, <3.12, <=*, <=5.15.*, <718178f524b98bc920d74bc771aed823c8b81425, 7.2, <47f0c7d856c67c9935546d2644f18c0d0131b449) 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/a4b9961efe8640f50800811b4a2b2046b3dc2ccc
- https://git.kernel.org/stable/c/8937b11f1c3896e066c3fb07387ba17bc8c50b8a
- https://git.kernel.org/stable/c/f1c675ecf6e5ad02722f0019f729d8bb588d502e
- https://git.kernel.org/stable/c/d5db3439ee8d1c165a09a47e984c4ba508c130df
- https://git.kernel.org/stable/c/b86666ac4009a252501cc17242582a7ec9ed976e
- https://git.kernel.org/stable/c/39151f0708c84221e94cdd6aa070aba5d7cb1c01
- https://git.kernel.org/stable/c/47f0c7d856c67c9935546d2644f18c0d0131b449
- https://git.kernel.org/stable/c/718178f524b98bc920d74bc771aed823c8b81425
