What happened
Git for Windows is the Windows port of Git. Prior to 2.55.0.windows.4, a malicious remote Git server can advertise a bundle URI that reaches transport_get_remote_bundle_uri(), fetch_bundle_uri_internal(), and copy_uri_to_file() in bundle-uri.c during clone or fetch when transfer.bundleuri=true. Non-HTTP(S) values are treated as local filesystem paths, and file URI prefixes are removed, so a bare UNC path or file URI targeting an attacker-controlled share causes Windows to initiate an outbound SMB connection. This can expose NTLM authentication material to the attacker-selected host. This issue is fixed in version 2.55.0.windows.4.
Affected versions
git: < 2.55.0.windows.4 Fixed: See vendor advisory.
Why it matters
Review the vendor advisory and exposure of the affected product to determine operational impact.
Detection & mitigation
- Apply vendor-provided updates or mitigations.
- Review affected product exposure and access logs.
Public PoC references
No public PoC reference has passed the current publication threshold.