CVE-2026-90333

About vulnerability

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

dm-integrity: replace forgeable discard filler with a keyed sector marker

The discard-block check in dm_integrity_rw_tag() treats a stored tag of all 0xf6 bytes (DISCARD_FILLER) as proof a block was discarded and skips HMAC verification. allow_discards is only accepted in dm-integrity’s standalone mode. An attacker with raw write access to the backing device, but without the integrity key, can stamp any block with an all-0xf6 tag and have it served as authentic.

Add a new “allow_discards_keyed” target argument that marks discarded blocks with a keyed checksum of (salt || sector) instead, computed by integrity_discard_checksum().

Affected product:

AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , Debian 11 ELS , TuxCare 9.6 ESU , TuxCare 9.8 ESU

Affected packages:

linux @ 5.10.259 (+7 more)