Python interpreter sandbox bypass in IBM Langflow OSS (CVE-2026-13435)

IBM Langflow OSS contains an improper input validation vulnerability in its PythonREPL sandbox implementation that allows an attacker with input access to a deployed flow or agent to bypass the code validator. Successful exploitation can expose sensitive server-side data including provider API keys, database credentials, and JWT signing and encryption key material. Under the default HS256 JWT configuration, exposure of that key material may further allow an attacker to forge valid access tokens and decrypt stored credentials. Affected versions: - 1.0.0-1.10.1 We recommend updating to: 1.10.2. CVSS 9.9 · our assessment: act_now Reference: https://www.ibm.com/support/pages/node/7279987 Details: https://vuln.today/cve/CVE-2026-13435