CVE-2026-57081
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
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 7.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.49%
- Percentil entre todas las CVEs puntuadas: 40
- Fecha de la puntuación: 5/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1190Exploit Public-Facing Applicationinitial access95 % - Impacto principal
T1499.004Application or System Exploitationimpact90 %
Vector AV:N/AC:L/PR:N indica explotación remota sin privilegios (T1190). CWE-400 (gestión de recursos) y descripción explícita de agotamiento de memoria (150 KB dispara gigabytes) con terminación del cliente son T1499.004 (DoS por consumo de recursos).
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-400, CWE-674
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-57081",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-57081",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
"technicalImpact": "partial"
}
],
"version": "2.0.3",
"timestamp": "2026-06-30T15:04:09.539220Z"
}
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.5,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "NONE"
},
"impactScore": 3.6,
"exploitabilityScore": 3.9
}
]
},
"affected": [
{
"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
"affectedData": [
{
"repo": "https://github.com/sanko/Net-BitTorrent.pm",
"vendor": "SANKO",
"product": "Net::BitTorrent",
"versions": [
{
"status": "affected",
"version": "0",
"versionType": "custom",
"lessThanOrEqual": "2.1.0"
}
],
"packageName": "Net-BitTorrent",
"programFiles": [
"lib/Net/BitTorrent/Protocol/BEP03/Bencode.pm"
],
"collectionURL": "https://cpan.org/modules",
"defaultStatus": "unaffected",
"programRoutines": [
{
"name": "Net::BitTorrent::Protocol::BEP03::Bencode::bdecode"
}
]
}
]
}
],
"published": "2026-06-30T12:16:25.633",
"references": [
{
"url": "https://github.com/sanko/Net-BitTorrent.pm/security/advisories/GHSA-mv44-v82p-89xv",
"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
},
{
"url": "https://metacpan.org/release/SANKO/Net-BitTorrent-v2.1.0/changes",
"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
}
],
"vulnStatus": "Deferred",
"weaknesses": [
{
"type": "Secondary",
"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
"description": [
{
"lang": "en",
"value": "CWE-400"
},
{
"lang": "en",
"value": "CWE-674"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Net::BitTorrent versions through 2.1.0 for Perl allow remote memory exhaustion via deeply nested bencoded input.\n\nbdecode 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.\n\nA 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."
}
],
"lastModified": "2026-07-20T07:16:39.117",
"sourceIdentifier": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
}