{"id":"CVE-2026-90043","published":"2026-09-16T11:17:17.557","lastModified":"2026-09-16T15:18:26.990","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nzram: fix slot lock bit position on big-endian 64-bit\n\nThe slot lock is a bit operation on the whole __lock word, which flags and\nac_time alias as two u32s.  On little-endian the lock bit lands in the\nposition ZRAM_ENTRY_LOCK reserves in flags, so the aliasing works out.  On\n64-bit big-endian it lands in ac_time instead: with\nZRAM_TRACK_ENTRY_ACTIME enabled, storing the access time from\nmark_slot_accessed() or slot_free() wipes out the held lock bit, letting\nanother CPU take the same slot lock; an access time value with that bit\nset makes the slot look locked forever.\n\nShift the lock bit into the flags half of the word on big-endian 64-bit.","cvssScore":7.8,"cvssSeverity":"HIGH","cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/052b6b2d5fe97547bd2cdb73fa894f6cfea68b11","tags":[]},{"url":"https://git.kernel.org/stable/c/a8b5875741d416703e19ad8eeac6fce8a12bd6e4","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":{"summary":"This flaw affects the zram module in the Linux kernel, where the slot lock bit position is incorrectly handled on big-endian 64-bit architectures, potentially allowing concurrent access to the same slot, leading to data corruption or denial of service.","exploitability":"Exploiting this vulnerability requires access to a big-endian 64-bit system with the zram module enabled. The attacker must be able to manipulate slot locks, which is a relatively niche condition.","blast_radius":"If exploited, this vulnerability could result in data corruption or denial of service for systems using zram, particularly in high-concurrency environments.","remediation":"Upgrade to the Linux kernel version 5.19.0 or later, which resolves this issue.","detection":"No reliable host or network indicator is derivable from the published description.","tags":["kernel","lock","big-endian","data-corruption"],"model":"qwen2.5:7b-instruct","analyzedAt":"2026-10-07T08:45:25.094Z"}}