CVE Watch14 jul 2026

CVE-2024-58340

LangChain versions up to and including 0.3.1 contain a regular expression denial-of-service (ReDoS) vulnerability in the MRKLOutputParser.pa

CVSS

7.5

Alto

EPSS

0.4%

p33

KEV

—

Exploit Today

0-100

Publicado: 12 ene 2026 · Última mod.: 14 jul 2026 · CWE-1333

EPSS · 30d

0.4%EPSS · 30 días0.4%

2026-06-302026-07-20

Descripción técnica

LangChain versions up to and including 0.3.1 contain a regular expression denial-of-service (ReDoS) vulnerability in the MRKLOutputParser.parse() method (libs/langchain/langchain/agents/mrkl/output_parser.py). The parser applies a backtracking-prone regular expression when extracting tool actions from model output. An attacker who can supply or influence the parsed text (for example via prompt injection in downstream applications that pass LLM output directly into MRKLOutputParser.parse()) can trigger excessive CPU consumption by providing a crafted payload, causing significant parsing delays and a denial-of-service condition.

Referencias oficiales

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