CVE-2019-19275: Python Typed Ast

High severity, CVSS 7.5. EPSS: 3.3% chance of exploitation in the next 30 days.

typed_ast 1.3.0 and 1.3.1 has an ast_for_arguments out-of-bounds read. An attacker with the ability to cause a Python interpreter to parse Python source (but not necessarily execute it) may be able to crash the interpreter process. This could be a concern, for example, in a web-based service that parses (but does not execute) Python code. (This issue also affected certain Python 3.8.0-alpha prereleases.)

Affected products

• Python Typed Ast: version 1.3.0 only; version 1.3.1 only

Published 2019-11-26. Last modified 2026-06-17.