Vulnerability in sahlberg libsmb2

[ Description ]Official description

libsmb2 before 6.3 contains integer overflow vulnerabilities in the DCE/RPC NDR decoder in lib/dcerpc.c that allow heap out-of-bounds reads and writes. A malicious SMB server or machine-in-the-middle on unsigned connections can send crafted NetrShareEnum replies with wrapping actual_count or max_count values when clients call smb2_share_enum_async(), corrupting heap memory.

[ Fixes ]Fixes and patches

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ References ]References

• github.com/sahlberg/libsmb2
• github.com/sahlberg/libsmb2/commit/a79f6914cb5ed3f74293d15cdea901261ce179ff
• github.com/sahlberg/libsmb2/issues/496
• github.com/sahlberg/libsmb2/releases/tag/libsmb2-6.3
• hackmd.io/@haindpwn/libsmb2-dcerpc-ndr-count-overflow-oob
• www.vulncheck.com/advisories/libsmb2-before-6.3-integer-overflow-in-dce-rpc-ndr-decoder…