What’s Vulnerable › Vulnerabilities

CVE-2026-34043: Serialize JavaScript has CPU Exhaustion Denial of Service via crafted array-like objects

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-03-31 · updated 2026-06-17
• Weakness: CWE-400

Description

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

How to fix

Upgrade to a fixed version: yahoo Serialize 7.0.5. Check the vendor advisory for mitigations.

References

• https://github.com/yahoo/serialize-javascript/commit/f147e90269b58bb6e539cfdf3d0e20d6ad14204b
• https://github.com/yahoo/serialize-javascript/releases/tag/v7.0.5
• https://github.com/yahoo/serialize-javascript/security/advisories/GHSA-qj8w-gfj5-8c6v

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