Vulnerability Description
libsmb2 6.2+ is vulnerable to Buffer Overflow. When processing SMB2 chained PDUs (NextCommand), libsmb2 repeatedly calls smb2_add_iovector() to append to a fixed-size iovec array without checking the upper bound of v->niov (SMB2_MAX_VECTORS=256). An attacker can craft responses with many chained PDUs to overflow v->niov and perform heap out-of-bounds writes, causing memory corruption, crashes, and potentially arbitrary code execution. The SMB2_OPLOCK_BREAK path bypasses message ID validation.
CVSS Score
HIGH
Related Weaknesses (CWE)
References
- https://gist.github.com/ZjW1nd/0b95b63307ceee7890e88e4abc6f041e
- https://github.com/sahlberg/libsmb2
- https://github.com/sahlberg/libsmb2/blob/master/lib/compat.c#L569
- https://github.com/sahlberg/libsmb2/commit/5e75eebf922b338cdb548d60cffb3b997d2a1
FAQ
What is CVE-2025-57632?
CVE-2025-57632 is a vulnerability with a CVSS score of 7.5 (HIGH). libsmb2 6.2+ is vulnerable to Buffer Overflow. When processing SMB2 chained PDUs (NextCommand), libsmb2 repeatedly calls smb2_add_iovector() to append to a fixed-size iovec array without checking the ...
How severe is CVE-2025-57632?
CVE-2025-57632 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2025-57632?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.