CVE-2026-34043: Yahoo Serialize

High severity, CVSS 7.5. EPSS: 0.6% chance of exploitation in the next 30 days.

Serialize JavaScript to a superset of JSON that includes regular expressions and functions. Prior to version 7.0.5, there is a Denial of Service (DoS) vulnerability caused by CPU exhaustion. When serializing a specially crafted "array-like" object (an object that inherits from Array.prototype but has a very large length property), the process enters an intensive loop that consumes 100% CPU and hangs indefinitely. This issue has been patched in version 7.0.5.

Affected products

• Yahoo Serialize: before 7.0.5 (fixed in 7.0.5)

Published 2026-03-31. Last modified 2026-06-17.