CVE-2026-90246EPSS p5.3%
CVE-2026-90246CVE-2026-90246
Description
In the Linux kernel, the following vulnerability has been resolved:
apparmor: fix integer overflow in verify_tags() bounds check
verify_tags() validates the tagset table unpacked from a policy blob.
For each set it reads a count and checks that advancing the index by
that count stays inside sets.table[]:
u32 cnt = tags->sets.table[i];
if (i+cnt >= tags->sets.size) {
i, cnt and sets.size are all u32, so i+cnt is evaluated modulo 2^32.
sets.table[] is filled by unpack_tagsets() with aa_unpack_u32(), so
every entry is a raw unbounded 32-bit word taken from the policy blob,
and verify_tags() is the function that is supposed to validate it. A
count close to U32_MAX makes the sum wrap to a small value, the guard
passes, and the inner loop then walks sets.table[++i] past the end of
the kcalloc(size, sizeof(u32)) allocation.
Note that sets.size is bounded by 65535, because unpack_tagsets() reads
it with aa_unpack_array() as a u16, so the wrap cannot be reached by
growing the table; it
Scoring
| CVSS | 7.1 () |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H |
| EPSS | 0.17% probability of exploitation · percentile 5.3% · 2026-10-05T12:00:23Z |
| Last modified | 2026-09-18 |