Quick answers
- Is CVE-2026-8859 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-8859 being exploited in the wild.
- How severe is CVE-2026-8859?
- Critical severity, with a CVSS score of 9.9, published 17 July 2026.
- Which products and versions are affected?
- IBM Langflow OSS 1.0.0-1.10.0.
- Is there a fix for CVE-2026-8859?
- A patch was published on 2026-07-02: Fixed in version 1.10.1 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-8859 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-8859?
- Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A path traversal vulnerability (CWE-22) exists in the APIRequest component of IBM Langflow OSS when the 'Save to File' feature is enabled. The vulnerability stems from improper sanitization of filenames extracted from the 'Content-Disposition' header of an HTTP response before they are joined to a temporary directory path. An attacker who controls an external HTTP server can return a response with a crafted filename containing traversal sequences (e.g., '../'). This allows the attacker to write arbitrary files to any location accessible by the Langflow process. In Docker-based deployments, this can be escalated to Remote Code Execution (RCE) by writing malicious .pth files to the Python site-packages directory, which are executed upon container restart.
Affected products
- IBM Langflow OSS 1.0.0-1.10.0
Timeline
- 2026-07-02: disclosed: Initial publication of the security bulletin by IBM
- 2026-07-02: patched: Fixed in version 1.10.1
- 2026-07-17: advisory: NVD publication date