Vulnerability Description
Net::BitTorrent versions through 2.1.0 for Perl allow remote memory exhaustion via deeply nested bencoded input. bdecode recurses once per nested list or dictionary level with no depth cap, and each recursive call receives the remaining buffer by value while the list and dictionary branches capture the whole remainder, so every live recursion frame keeps its own copy of the shrinking buffer (O(N^2) bytes for an N-deep input). The decoder runs on every untrusted bencode source: .torrent files, BEP09 metadata fetched from peers, DHT messages, and tracker responses. A bencoded input of roughly 150,000 nested lists (about 150 KB on the wire) drives multi-gigabyte peak memory, so one short message from any peer, or one crafted .torrent file or magnet link, terminates the client.
CVSS Score
HIGH
Related Weaknesses (CWE)
References
- https://github.com/sanko/Net-BitTorrent.pm/security/advisories/GHSA-mv44-v82p-89
- https://metacpan.org/release/SANKO/Net-BitTorrent-v2.1.0/changes
FAQ
What is CVE-2026-57081?
CVE-2026-57081 is a vulnerability with a CVSS score of 7.5 (HIGH). Net::BitTorrent versions through 2.1.0 for Perl allow remote memory exhaustion via deeply nested bencoded input. bdecode recurses once per nested list or dictionary level with no depth cap, and each ...
How severe is CVE-2026-57081?
CVE-2026-57081 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-57081?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.