OpenLDAP Lightning Memory-Mapped Database (LMDB) versions 0.9.14 before 0.9.34, prior to commit 8e1fda8, contain a heap buffer underflow in the readline() function of mdb_load. When processing malformed input containing an embedded NUL byte, an unsigned offset calculation can underflow and cause an out-of-bounds read of one byte before the allocated heap buffer. This can cause mdb_load to crash, leading to a limited denial-of-service condition.
Fix
Patch, vendor advisory and mitigation references on NVD 1
- https://bugs.openldap.org/show_bug.cgi?id=10421 issue-tracking, patch
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 4.6 · openldap foundationNVD modified 2026-10-29 20:19
Affected (CPE criteria) 0
NVD has not attached CPE configurations yet.
References 5
- https://seclists.org/fulldisclosure/2026/Jan/5 technical-description, exploit
- https://seclists.org/fulldisclosure/2026/Jan/8 technical-description, exploit
- https://www.openldap.org/ product
- https://www.vulncheck.com/advisories/openldap-lmdb-mdb-load-heap-buffer-underflow-in-readline third-party-advisory
- https://bugs.openldap.org/show_bug.cgi?id=10421 issue-tracking, patch