CVE-2024-58340

HIGH EPSS 32.7%
Published Jan 12, 20265mo ago · Modified Jun 17, 20261w ago
8.7 CVSS 4.0
High
Find Similar
Published Jan 12, 2026 5mo ago
Last Modified Jun 17, 2026 1w ago

Description

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.

CVSS Details

Base Score
8.7
Exploitability
—
Impact
—
Vector string
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope X

Threat Intelligence

EPSS Exploit Probability
32.7% percentile
Exploit & Patch Status
Public Exploit Known
No Patch Available

Weaknesses 1

CWE-1333

Affected Products 1

VendorProductVersionRange
langchainlangchain* ≤0.3.1

References 4

  • github.com https://github.com/langchain-ai/langchain
    Product
  • huntr.com https://huntr.com/bounties/e7ece02c-d4bb-4166-8e08-6baf4f8845bb
    ExploitIssue TrackingThird Party Advisory
  • langchain.com https://www.langchain.com/
    Product
  • vulncheck.com https://www.vulncheck.com/advisories/langchain-mrkloutputparser-redos
    Third Party Advisory

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.