CVE-2024-58340 (GCVE-0-2024-58340)

Vulnerability from cvelistv5 – Published: 2026-01-12 23:05 – Updated: 2026-01-12 23:05
VLAI?
Title
LangChain <= 0.3.1 MRKLOutputParser ReDoS
Summary
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.
Severity ?
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CWE
  • CWE-1333 - Inefficient Regular Expression Complexity
Assigner
References
Impacted products
Vendor Product Version
LangChain AI LangChain Affected: 0 , ≤ 0.3.1 (semver)
Create a notification for this product.
Credits
LifeTeam2024
Show details on NVD website
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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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