Net::BitTorrent validates file path components only on the .torrent-file ingest path. The peer and magnet metadata path (_on_metadata_received, reached from the BEP09 ut_metadata extension) passes attacker-supplied file names straight to Storage::add_file and Storage::_parse_file_tree, where Path::Tiny's child() does not collapse "..". A v2 file tree key, a v1 files[].path element, or a single-file name containing ".." segments therefore resolves outside the download directory.
Because the peer also controls the piece hashes and the served bytes, content verification passes, so a malicious magnet or peer writes attacker-chosen content to an attacker-chosen path on the downloading host.
Analysis
Analysis and contextual insights are available on OpenCVE Cloud.
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| SANKO | Net::BitTorrent | unaffected |
|
No data.
No data.
No data available yet.
Vendor Workaround
There is no fixed release. Validate metadata file path components on the peer and magnet ingest path as the .torrent-file path already does (reject components equal to '', '.', or '..' or containing '/' or '\'), and confirm each resolved path stays within the download directory before writing.
Tracking
Sign in to view the affected projects.
No advisories yet.
Tue, 30 Jun 2026 14:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
cvssV3_1
|
Tue, 30 Jun 2026 11:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Net::BitTorrent versions through 2.0.1 for Perl write files outside the download directory via path traversal in peer-supplied metadata. Net::BitTorrent validates file path components only on the .torrent-file ingest path. The peer and magnet metadata path (_on_metadata_received, reached from the BEP09 ut_metadata extension) passes attacker-supplied file names straight to Storage::add_file and Storage::_parse_file_tree, where Path::Tiny's child() does not collapse "..". A v2 file tree key, a v1 files[].path element, or a single-file name containing ".." segments therefore resolves outside the download directory. Because the peer also controls the piece hashes and the served bytes, content verification passes, so a malicious magnet or peer writes attacker-chosen content to an attacker-chosen path on the downloading host. | |
| Title | Net::BitTorrent versions through 2.0.1 for Perl write files outside the download directory via path traversal in peer-supplied metadata | |
| Weaknesses | CWE-22 | |
| References |
|
Subscriptions
No data.
MITRE
Status: PUBLISHED
Assigner: CPANSec
Published:
Updated: 2026-06-30T13:52:04.135Z
Reserved: 2026-06-23T18:20:33.513Z
Link: CVE-2026-57079
Vulnrichment
Updated: 2026-06-30T13:51:56.088Z
NVD
No data.
Redhat
No data.
OpenCVE Enrichment
Updated: 2026-06-30T12:30:13Z