CVE-2026-98171

HIGH
8.8CVSS v3
—CVSS v2
0.51% EPSS (exploit probability)
—CWE

Description

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

smb: client: fix next_buffer UAF and NextCommand bounds in compound PDUs

Fix several related bounds checking and pointer lifecycle issues in
receive_encrypted_standard()'s handling of compound encrypted frames:

- Clear next_buffer after assigning it to server->bigbuf. A stale
next_buffer pointer can lead to a use-after-free on subsequent
error paths.
- Update pdu_length to the decrypted plaintext size (buf_size). Using
the pre-decryption length allows NextCommand to point into stale
ciphertext residue.
- Reject next_cmd values smaller than MID_HEADER_SIZE(server).
- Fix an integer overflow in the upper bound check by verifying
pdu_length - next_cmd < MID_HEADER_SIZE(server), ensuring the
trailing slice is large enough for a header.

CVSS v3 vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Affected routers (0)

No routers currently mapped to this CVE in our database.

External references