Threat Intelligence Database

Dulwich's porcelain.checkout(paths=[...]) function uses raw os.open calls that follow symlinks, bypassing symlink protections and allowing arbitrary file writes. An attacker can craft a malicious repository with symlinks that cause checkout to overwrite files such as .git/hooks/post-checkout, enabling remote code execution on subsequent git operations. The vulnerability affects Poetry versions from 2.2.0 up to but not including 2.4.2. A patch is available to fix this issue by replacing the raw os.open usage with a safer method that detects symlinks.

Dulwich's stash pop function in version 1.2.7 is vulnerable to a symlink directory traversal that allows an attacker to write arbitrary files outside the repository worktree. This occurs because the function uses os.path.exists() which follows symlinks, enabling writes through malicious intermediate symlinks. An attacker can craft a repository that, when a victim pops a stash, writes attacker-controlled files such as .git/hooks/post-checkout, leading to remote code execution on the victim's machine during subsequent git operations. A patch is available to mitigate this issue by verifying symlink resolution before writing files.

A denial of service (DoS) vulnerability exists in the dulwich library's Pack.resolve_object method. When resolving an OFS_DELTA object with a delta_offset of zero, the method enters an infinite recursive loop due to self-referential offset calculation. This causes CPU exhaustion and process crashes in applications using dulwich for Git packfile operations. The vulnerability affects dulwich versions >=1.2.0 and <2.4.2. A patch is available to explicitly reject delta_offset == 0 and prevent infinite recursion.

Dulwich's filter_branch.py in Poetry versions 2.2.0 up to but not including 2.4.2 contains a symlink directory traversal vulnerability in the CommitFilter._apply_index_filter() function. This occurs because materialized tree entries, including symlinks, persist in the working directory between commits, allowing an attacker to redirect file writes to arbitrary filesystem locations. An attacker can exploit this by crafting a malicious repository that causes filter_branch to write attacker-controlled content to arbitrary locations, potentially achieving remote code execution if writes target .git/hooks/. A fix is available that involves cleaning the working directory between commit iterations or verifying symlinks before writing files.