Description
libsmb2 through 6.2 contains an integer underflow vulnerability in decode_acl that allows malicious SMB servers to trigger heap out-of-bounds reads via crafted security descriptors. Attackers controlling a server or intercepting unsigned sessions can send an AclSize below 8 in a QUERY_INFO reply, bypassing ACE bounds checks and crashing the client.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
sahlberg libsmb2
Default version status: unaffected
0 to ≤ 6.2affected
References
- https://hackmd.io/@haind-pwn/libsmb2-query-info-reply-oob-read ↗
- https://github.com/sahlberg/libsmb2/blob/d67e213a5c4e7e4969fd81f0b95e4ca5831fbba1/lib/smb2-data-security-descriptor.c#L266 ↗
- https://github.com/sahlberg/libsmb2/commit/523abe20be3207011a936db47f1d3bab79c05450 ↗
- https://github.com/sahlberg/libsmb2 ↗
- https://www.vulncheck.com/advisories/libsmb2-through-6.2-heap-out-of-bounds-read-via-decode-acl-integer-underflow ↗