TorrentPier Deserialization of Untrusted Data vulnerabilityGHSA-fg86-4c2r-7wxw
CRITICALFix: torrentpier/torrentpier@ed37e6eGHSA-fg86-4c2r-7wxw is a critical-severity (CVSS 9.8) Deserialization of Untrusted Data vulnerability in torrentpier/torrentpier. A fix is available for torrentpier/torrentpier — see the affected versions and patch details below.
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for GHSA-fg86-4c2r-7wxw.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
torrentpier/torrentpierReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
TorrentPier is an open source BitTorrent Public/Private tracker engine, written in php. In torrentpier/library/includes/functions.php, get_tracks() uses the unsafe native PHP serialization format to deserialize user-controlled cookies. One can use phpggc and the chain Guzzle/FW1 to write PHP code to an arbitrary file, and execute commands on the system. For instance, the cookie bb_t will be deserialized when browsing to viewforum.php. This issue has been addressed in commit ed37e6e52 which is expected to be included in release version 2.4.4. Users are advised to upgrade as soon as the new release is available. There are no known workarounds for this vulnerability.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | torrentpier/torrentpier | all versions | 2.4.4composer require torrentpier/torrentpier:^2.4.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for torrentpier/torrentpier, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update torrentpier/torrentpier to 2.4.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-fg86-4c2r-7wxw is resolved across your whole dependency graph.
Workarounds
Do not deserialise data from untrusted sources: where the format allows it, restrict deserialisation to an explicit allowlist of expected types, and prefer a data-only format (JSON, Protobuf) over one that can reconstruct arbitrary objects until you can upgrade.
Frequently Asked Questions
Is GHSA-fg86-4c2r-7wxw in your dependencies?
Find it across Packagist, including transitive dependencies.