CVE-2026-79707

CVE-2026-79707 is a path traversal flaw (CWE-22) in the builder endpoint of Google Cloud's Agent Development Kit (ADK) for Python, affecting versions 1.9.0 through 1.21.0. An unauthenticated remote attacker triggers it by sending a crafted file_path query parameter to the builder endpoint, causing the server to resolve paths outside its intended directory. The attacker gains the ability to read arbitrary files accessible to the ADK process, such as application configuration, source code, or credentials; per the CVSS 4.0 score of 8.7 (high) the impact is limited to confidentiality, with no integrity or availability impact and no code execution. Anyone running ADK for Python 1.9.0 through 1.21.0 with the builder endpoint reachable by untrusted clients is affected, with locally bound development instances largely shielded from remote attack. There is no known public proof-of-concept, the issue is not in CISA's KEV catalog, and EPSS puts 30-day exploitation probability at roughly 0.4%, so no confirmed exploitation is known.

What to do: Upgrade ADK for Python to a release newer than 1.21.0, which is outside the affected range. Until patched, restrict the builder endpoint to localhost or trusted networks (e.g., via reverse-proxy allowlisting or authentication) and ensure the ADK process cannot read sensitive files such as credentials. Review access logs for requests to the builder endpoint containing file_path parameters with traversal sequences such as ../ or encoded variants, which would indicate probing or exploitation.