Is CVE-2026-104020 being exploited?

No public exploit is currently tracked.

How severe is CVE-2026-104020?

CVE-2026-104020 has a CVSS v3 severity of HIGH (7.5).

Back

CVE-2026-104020

Description

Uncontrolled recursion in the Ion reader in Amazon Ion Python before 0.15.0 might allow a remote unauthenticated actor to crash the application using the library, resulting in a denial of service, via a crafted, deeply nested Ion value. To remediate this issue, users should upgrade to version 0.15.0 or later.