---
cve: "CVE-2026-90043"
severity: "HIGH"
cvss: 7.8
epss: "0.1%"
vendor: "Linux"
kev: false
exploited: false
published: "2026-09-16 10:33:40"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-21T05:37:00+02:00"
---

# CVE-2026-90043

> 7.8 HIGH

## Beschreibung

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

zram: fix slot lock bit position on big-endian 64-bit

The slot lock is a bit operation on the whole __lock word, which flags and
ac_time alias as two u32s.  On little-endian the lock bit lands in the
position ZRAM_ENTRY_LOCK reserves in flags, so the aliasing works out.  On
64-bit big-endian it lands in ac_time instead: with
ZRAM_TRACK_ENTRY_ACTIME enabled, storing the access time from
mark_slot_accessed() or slot_free() wipes out the held lock bit, letting
another CPU take the same slot lock; an access time value with that bit
set makes the slot look locked forever.

Shift the lock bit into the flags half of the word on big-endian 64-bit.

## CVSS-Vektor

```
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Lokal | good |
| AC Komplexität | Gering | bad |
| PR Privilegien | Gering | warn |
| UI Interaktion | Keine | bad |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Hoch | bad |
| I Integrität | Hoch | bad |
| A Verfügbarkeit | Hoch | bad |

## Patch verfügbar (OSV)

- Kernel ≥ 7.2.5

## Referenzen

- <https://git.kernel.org/stable/c/052b6b2d5fe97547bd2cdb73fa894f6cfea68b11>
- <https://git.kernel.org/stable/c/a8b5875741d416703e19ad8eeac6fce8a12bd6e4>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-90043) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_