---
cve: "CVE-2026-74350"
severity: "CRITICAL"
cvss: 9.8
epss: "0.7%"
vendor: "Linux"
kev: false
exploited: false
published: "2026-08-15 06:22:36"
tags: [cve, security, critical]
source: tsecurity.de CVE-Dossier
exported: "2026-11-01T17:15:15+01:00"
---

# CVE-2026-74350

> 9.8 CRITICAL

## Beschreibung

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

ocfs2: validate fast symlink target during inode read

ocfs2_validate_inode_block() already rejects several inconsistent
self-contained dinodes before they are exposed to the rest of the
filesystem.  Fast symlinks need the same treatment.

A zero-cluster symlink is treated as a fast symlink and later read through
page_get_link() and ocfs2_fast_symlink_read_folio().  That path uses
strnlen() on the inline payload and then copies len + 1 bytes into the
folio.  If a corrupt dinode stores an i_size that does not fit the inline
area or omits the terminating NUL at i_size, that copy reads past the end
of the inode block buffer.

Reject zero-cluster symlink dinodes whose i_size exceeds the inline
fast-symlink capacity or whose inline payload is not NUL-terminated
exactly at i_size when the inode block is validated.  This keeps malformed
fast symlinks from reaching the read path.

Validation reproduced this kernel report:
KASAN use-after-free in ocfs2_fast_symlink_read_folio+0x12c/0x1f0
RIP: 0033:0x7f5c6d859aa7
Read of size 3905
Call trace:
  dump_stack_lvl+0x66/0xa0 (?:?)
  print_report+0xce/0x630 (?:?)
  ocfs2_fast_symlink_read_folio+0x12c/0x1f0 (fs/ocfs2/inode.c:?)
  srso_alias_return_thunk+0x5/0xfbef5 (?:?)
  __virt_addr_valid+0x19f/0x330 (?:?)
  kasan_report+0xe0/0x110 (?:?)
  kasan_check_range+0x105/0x1b0 (?:?)
  __asan_memcpy+0x23/0x60 (?:?)
  filemap_read_folio+0x27/0xe0 (?:?)
  filemap_read_folio+0x35/0xe0 (?:?)
  do_read_cache_folio+0x138/0x230 (?:?)
  __page_get_link+0x26/0x110 (?:?)
  page_get_link+0x2e/0x70 (?:?)
  vfs_readlink+0x15e/0x250 (?:?)
  touch_atime+0x4d/0x370 (?:?)
  do_readlinkat+0x186/0x200 (?:?)
  do_user_addr_fault+0x65a/0x890 (?:?)
  __x64_sys_readlink+0x46/0x60 (?:?)
  do_syscall_64+0x115/0x6a0 (arch/x86/entry/syscall_64.c:87)
  entry_SYSCALL_64_after_hwframe+0x77/0x7f (?:?)

## CNA-Record (Kanon, cvelistV5)

- CNA: **Linux**
- State: PUBLISHED
- Stand: 2026-10-30 12:29:50
- CNA-CVSS: **9.8** (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)

## CVSS-Vektor

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

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

## Patch verfügbar (OSV)

- Kernel ≥ 6.1.191
- Kernel ≥ 6.6.160
- Kernel ≥ 6.12.114
- Kernel ≥ 6.18.57
- Kernel ≥ 7.1.5

## BSI-Hinweise (deutsch)

- [Linux Kernel: Mehrere Schwachstellen](https://wid.cert-bund.de/portal/wid/sicherheitshinweis/WID-SEC-W-2026-2852) — _BSI-Einstufung: hoch_
  Ein Angreifer kann mehrere Schwachstellen in Linux Kernel ausnutzen, um einen Denial of Service herbeizuführen oder einen nicht näher spezifizierten Angriff durchzuführen.

## Referenzen

- <https://git.kernel.org/stable/c/dcabbf7da43825e23e5e89adccc1430faee1bce1>
- <https://git.kernel.org/stable/c/030d4caae89977b80349df95523dfda1dfb10f73>
- <https://git.kernel.org/stable/c/d94bf50756d7f80bb728ad58246376649e1035b6>
- <https://git.kernel.org/stable/c/f9e2cb692b77a679b1f4cc2b7b277fa908586533>
- <https://git.kernel.org/stable/c/e234973f286ed2e8961a24561ec91594ec3e3ff8>
- <https://git.kernel.org/stable/c/ed9f95ee3bbaea9b05808727eb86ea5e5ccf2b52>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/sicherheitsluecken/cve-2026-74350/) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_