High severity · published Mar 31, 2026
CVE-2026-34043
Serialize JavaScript has CPU Exhaustion Denial of Service via crafted array-like objects
7.5
CVSS
0.5%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 41% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SE
serialize-javascript · yahoo
< 7.0.5 · source: vendor
SE
Serialize · Yahoo
before 7.0.5 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-34043
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-34043
Patch
https://github.com/yahoo/serialize-javascript/commit/f147e90269b58bb6e539cfdf3d0e20d6ad14204b
Release Notes
https://github.com/yahoo/serialize-javascript/releases/tag/v7.0.5
Vendor Advisory
https://github.com/yahoo/serialize-javascript/security/advisories/GHSA-qj8w-gfj5-8c6v
More from serialize-javascript
4.7
CVE-2026-115754
serialize-javascript 7.0.1 before 7.1.3 XSS via unescaped </script in function body
2.3
CVE-2026-97711
Serialize JavaScript: Cross-site scripting (XSS) via unescaped </script> in serialized function bodies
2.1
CVE-2026-115897
Serialize JavaScript: Cross-site scripting (XSS) via unescaped </script at the end of a serialized function body