Vulnerability · Published Jun 30, 2026 · Assigned by VulnCheck

CVE-2026-58166OpenBMB ChatDev - Unauthenticated Path Traversal in Upload Handler Allows Arbitrary File Write and Delete

Critical 9.1

In plain English

A critical-severity path traversal in ChatDev from OpenBMB. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.9% (higher than 58% of all known vulnerabilities).

Severity (CVSS 3.1)9.1Critical

Exploit odds (30 days)0.9%top 41.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

OpenBMB ChatDev through 2.2.0, fixed in commit 4fd4da6, contains a path traversal vulnerability that allows unauthenticated remote attackers to write or delete arbitrary files by supplying a malicious multipart filename in the file upload endpoint. Attackers can send a crafted filename containing path traversal sequences or an absolute path to the POST uploads session endpoint, which constructs the destination path without sanitization in save_upload_file, causing file write and cleanup operations to target attacker-chosen paths on the server filesystem.

Affected products (as reported)

Vendor	Product	Versions
OpenBMB	ChatDev	0 – through 2.2.0

Weakness: CWE-22 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H

References

Researcher Disclosure technical-description, exploit
Fix PR issue-tracking
Fix Commit patch
https://www.vulncheck.com/advisories/openbmb-chatdev-unauthenticated-path-traversal-in-upload-handler-allows-arbitrary-file-write-and-delete third-party-advisory