CVE-2026-55443

What it is

LangChain is a framework for building agents and LLM-powered applications. Prior to 1.3.9, several LangChain components that resolve filesystem paths or expand search patterns do not consistently confine the resolved path to the intended root directory. Affected behaviors include: a file-search agent middleware that validates a starting directory but not the search pattern or the resolved target of matched files, so glob patterns and symlinks can reach files outside the configured root; prompt- and chain/agent-configuration loaders that accept path fields and resolve them without confining the result to a trusted base or rejecting symlink targets; and path-prefix authorization checks that compare by string prefix without a path-segment boundary, so a sibling path sharing the prefix is accepted. When these components receive path values, search patterns, or workspace contents influenced by an untrusted source — including an LLM acting on untrusted input — the result can be disclosure of files outside the intended boundary. This vulnerability is fixed in 1.3.9.

At a glance

Exploitability

Can be exploited locally on the machine without logging in. High risk of data exposure.

Exploit odds

0.2% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-06-22 19:17 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-26 20:05 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 0.2% in the next 30 days (EPSS).
• Severity: 5.1 MEDIUM (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2026-06-22 19:17 UTC

Last modified

2026-06-26 20:05 UTC

Exploit probability

0.2% · EPSS, next 30 days

Weakness

CWE-22 · Path traversal

Record status

Analyzed

Affected

• Langchain < 1.3.9

Attack profile CVSS 3.1 · 5.1

Attack vector

Local

Complexity

High

Privileges needed

None

User interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

None

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2026-55443.md and follow it. Check whether this project is affected by CVE-2026-55443. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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