---
cve: "CVE-2026-89839"
severity: "LOW"
cvss: 3.1
epss: "0.2%"
vendor: "Linux"
kev: false
exploited: false
published: "2026-09-16 11:16:50"
tags: [cve, security, low]
source: tsecurity.de CVE-Dossier
exported: "2026-09-20T20:04:20+02:00"
---

# CVE-2026-89839

> 3.1 LOW

## Beschreibung

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

f2fs: use the mount idmap for the owner check in f2fs_xattr_advise_set()

f2fs_xattr_advise_set() calls inode_owner_or_capable() with &nop_mnt_idmap
before allowing the "system.advise" xattr to be set, instead of the idmap
that the VFS passes to the ->set() handler.

f2fs supports idmapped mounts, so on such a mount this checks the caller's
fsuid against the unmapped on-disk owner rather than the mapped owner: the
actual owner can be wrongly denied with -EPERM and an unrelated caller
wrongly allowed.  Pass the handler's idmap instead.

## Patch verfügbar (OSV)

- Kernel ≥ 6.6.157
- Kernel ≥ 6.12.110
- Kernel ≥ 6.18.51
- Kernel ≥ 7.2.5

## Referenzen

- <https://git.kernel.org/stable/c/4c0c610b480cfbc57528aa1acbd6be12ed2a6fb1>
- <https://git.kernel.org/stable/c/c3e2692c7a58e0bdb84bd658d827e89dcecea3ad>
- <https://git.kernel.org/stable/c/3b681229e9f8fb1dd29bc65983bf3c87779e4ca3>
- <https://git.kernel.org/stable/c/ab31e3b774f5d06b4489cef6c297b48c47c9dcbd>
- <https://git.kernel.org/stable/c/a54ffce4637acb0db8e695188a6c7f99f14c3576>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-89839) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_