CVE-2026-53587 - libgit2 - Unauthenticated network-reachable heap out-of-bounds read in transports/smart_pkt.c:set_data
Brief
CVE ID : CVE-2026-53587
Published : Aug. 20, 2026, 6:36 p. m.
- 32 minutes ago
Description : libgit2 is a portable C implementation of the Git core methods provided as a linkable library with a solid API, allowing to build Git functionality into your application. Prior to 1.
- 6 and 1.
- 5, libgit2 performs a fixed-size strncmp in set_data in src/libgit2/transports/smart_pkt. c without first verifying that the smart-protocol pkt-line capability buffer contains 14 bytes.
A malicious Git server can make bytes after the pkt-line complete object-format=, causing format_str to advance beyond the pkt-line and the following memchr length calculation to underflow. The resulting heap out-of-bounds walk can crash a client during the first refs-advertisement packet over HTTP, HTTPS, SSH, or the Git protocol. This issue is fixed in versions 1.
- 6 and 1.
- 5.