CVE-2024-58340 (GCVE-0-2024-58340)
Vulnerability from cvelistv5 – Published: 2026-01-12 23:05 – Updated: 2026-07-14 22:54
VLAI
EPSS
VEX
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
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-13 16:21 UTC
CWE
- CWE-1333 - Inefficient Regular Expression Complexity
Assigner
VulnCheck
CNA
References
4 references
| URL | Tags |
|---|---|
| https://huntr.com/bounties/e7ece02c-d4bb-4166-8e0… | technical-descriptionexploit |
| https://www.langchain.com/ | product |
| https://github.com/langchain-ai/langchain | product |
| https://www.vulncheck.com/advisories/langchain-mr… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| LangChain AI | LangChain |
Affected:
0 , ≤ 0.3.1
(semver)
cpe:2.3:a:langchain:langchain_core:*:*:*:*:*:python:*:* |
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Nomenclature
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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