CVE-2026-57081 (GCVE-0-2026-57081)
Vulnerability from cvelistv5 – Published: 2026-06-30 11:05 – Updated: 2026-06-30 15:04
VLAI
Title
Net::BitTorrent versions through 2.0.1 for Perl allow remote memory exhaustion via deeply nested bencoded input
Summary
Net::BitTorrent versions through 2.0.1 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)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator (v2.0.3)
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/sanko/Net-BitTorrent.pm/securi… | vendor-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| SANKO | Net::BitTorrent |
Affected:
0 , ≤ 2.0.1
(custom)
|
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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