CVE-2026-76219

GitPython versions before 3.1.58 contain an arbitrary file overwrite vulnerability in IndexFile.from_tree, IndexFile.reset, and IndexFile.merge_tree methods that append caller-influenced treeish strings to git read-tree without option validation or argument separation. Attackers can inject the --index-output option to overwrite arbitrary files with a valid git-index blob, destroying existing file content at attacker-controlled writable paths.