CVE-2026-31614
Gravedad:
Pendiente de análisis
Tipo:
No Disponible / Otro tipo
Fecha de publicación:
24/04/2026
Última modificación:
27/04/2026
Descripción
*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br />
<br />
smb: client: fix off-by-8 bounds check in check_wsl_eas()<br />
<br />
The bounds check uses (u8 *)ea + nlen + 1 + vlen as the end of the EA<br />
name and value, but ea_data sits at offset sizeof(struct<br />
smb2_file_full_ea_info) = 8 from ea, not at offset 0. The strncmp()<br />
later reads ea->ea_data[0..nlen-1] and the value bytes follow at<br />
ea_data[nlen+1..nlen+vlen], so the actual end is ea->ea_data + nlen + 1<br />
+ vlen. Isn&#39;t pointer math fun?<br />
<br />
The earlier check (u8 *)ea > end - sizeof(*ea) only guarantees the<br />
8-byte header is in bounds, but since the last EA is placed within 8<br />
bytes of the end of the response, the name and value bytes are read past<br />
the end of iov.<br />
<br />
Fix this mess all up by using ea->ea_data as the base for the bounds<br />
check.<br />
<br />
An "untrusted" server can use this to leak up to 8 bytes of kernel heap<br />
into the EA name comparison and influence which WSL xattr the data is<br />
interpreted as.
Impacto
Referencias a soluciones, herramientas e información
- https://git.kernel.org/stable/c/3d8b9d06bd3ac4c6846f5498800b0f5f8062e53b
- https://git.kernel.org/stable/c/5cc0574c84aa73946ade587c41e81757b8b01cb5
- https://git.kernel.org/stable/c/a893f1757d9a4009e4a8d7ceb2312142fe29cea4
- https://git.kernel.org/stable/c/b2b76d09a64c538c57006180103fc1841e8cfa66
- https://git.kernel.org/stable/c/ba3ad159aa61810bbe0acaf39578b1ebfb6f1a18
- https://git.kernel.org/stable/c/bfbc74df8bbe095b3ed68f6d4487b368af087890



