CVE-2026-34371: LibreChat Affected by Arbitrary File Write via `execute_code` Artifact Filename Traversal

Severity: medium (CVSS 6.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-04-07 · updated 2026-07-24
Weakness: CWE-22

Description

LibreChat is a ChatGPT clone with additional features. Prior to 0.8.4, LibreChat trusts the name field returned by the execute_code sandbox when persisting code-generated artifacts. On deployments using the default local file strategy, a malicious artifact filename containing traversal sequences (for example, ../../../../../app/client/dist/poc.txt) is concatenated into the server-side destination path and written with fs.writeFileSync() without sanitization. This gives any user who can trigger execute_code an arbitrary file write primitive as the LibreChat server user. This vulnerability is fixed in 0.8.4.

Affected products

danny-avila LibreChat: before 0.8.4 — fixed in 0.8.4

How to fix

Upgrade to a fixed version: danny-avila LibreChat 0.8.4. Check the vendor advisory for mitigations.

References

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