CVE-2026-57081 (GCVE-0-2026-57081)

Vulnerability from cvelistv5 – Published: 2026-06-30 11:05 – Updated: 2026-07-20 06:42
VLAI
Title
Net::BitTorrent versions through 2.1.0 for Perl allow remote memory exhaustion via deeply nested bencoded input
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-30 15:04 UTC
CWE
  • CWE-674 - Uncontrolled Recursion
  • CWE-400 - Uncontrolled Resource Consumption
Assigner
CPANSec CNA under the redhat root
CNA scorecard C 61/100 over 362 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
SANKO Net::BitTorrent Affected: 0 , ≤ 2.1.0 (custom)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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