In the Linux kernel, the following vulnerability has been resolved:
ksmbd: use check_add_overflow() to prevent u16 DACL size overflow
set_posix_acl_entries_dacl() and set_ntacl_dacl() accumulate ACE sizes
in u16 variables. When a file has many POSIX ACL entries, the
accumulated size can wrap past 65535, causing the pointer arithmetic
(char )pndace + size to land within already-written ACEs. Subsequent
writes then overwrite earlier entries, and pndacl->size gets a
truncated value.
Use check_add_overflow() at each accumulation point to detect the
wrap before it corrupts the buffer, consistent with existing
check_mul_overflow() usage elsewhere in smbacl.c.
| Score | Percentile |
|---|---|
| 0.01% | 3.39% |
| Base score | Version | Severity | Vector |
|---|---|---|---|
| 5.5 | 3.1 | — |
|
| Type | Value |
|---|---|
| GHSA | GHSA-xmgr-rx43-m3gf ↗ |
| CVE | CVE-2026-31704 ↗ |