CPANSA-Net-BitTorrent-2026-57080: Net-BitTorrent vulnerability

Publisher giterlizzi Document category csaf_security_advisory
Initial release date 2026-06-30T00:00:00 Engine CSAF Perl Toolkit 0.26
Current release date 2026-06-30T00:00:00 Build Date
Current version 1 Status final
CVSS v3.1 Base Score 7.5 Severity
Original language Language en
Also referred to

Vulnerability Description

Net::BitTorrent versions through 2.0.1 for Perl allow remote memory exhaustion via an uncapped peer-wire message-length prefix. The peer-wire framing in _process_messages trusts the 4-byte length prefix sent by a connected peer with no upper bound, while receive_data appends every inbound byte to the input buffer. A peer announces a length prefix of up to about 4 GiB and then streams bytes; the decoder waits until the buffer holds the full message before processing it, so the buffer grows without limit. Peer connections are unauthenticated, so any peer in the swarm exhausts the downloading process's memory. The largest legitimate message is a 16 KiB piece block, so any announced length far above that is anomalous.

Vulnerabilities

CVE-2026-57080

Vulnerability Description

Net::BitTorrent versions through 2.0.1 for Perl allow remote memory exhaustion via an uncapped peer-wire message-length prefix.

The peer-wire framing in _process_messages trusts the 4-byte length prefix sent by a connected peer with no upper bound, while receive_data appends every inbound byte to the input buffer. A peer announces a length prefix of up to about 4 GiB and then streams bytes; the decoder waits until the buffer holds the full message before processing it, so the buffer grows without limit.

Peer connections are unauthenticated, so any peer in the swarm exhausts the downloading process's memory. The largest legitimate message is a 16 KiB piece block, so any announced length far above that is anomalous.

Weakness CWE-400 : Uncontrolled Resource Consumption

Product status

Known affected
Product Score
Net-BitTorrent greater than 0
CVSS Version CVSS Vector CVSS Base Score CVSS Base Severity
3.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H 7.5 High

giterlizzi

Namespace: https://github.com/giterlizzi/

gdt@cpan.org

References

Revision history

Version Date of the revision Summary of the revision
1 Tue Jun 30 00:00:00 2026 First release

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