XSS in Yahoo Serialize-Javascript
CVE-2026-115754
serialize-javascript from 7.0.1 before 7.1.3 contains a cross-site scripting vulnerability that allows attackers to break out of HTML script elements by ending serialized function source text with an unescaped </script. Attackers controlling a function's source via a spoofed toString() can combine surrounding output delimiters and later values to inject live markup such as img onerror handlers.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.7 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/yahoo/serialize-javascript/security/advisories/GHSA-m5mm-p8h7-m29v (vendor-advisory)
- github.com/yahoo/serialize-javascript/pull/235 (issue-tracking, patch)
- github.com/yahoo/serialize-javascript/commit/2864b3c6260a3bfd52d2db3e70d1a079de… (patch)
- github.com/yahoo/serialize-javascript/releases/tag/v7.1.3 (release-notes)
- www.vulncheck.com/advisories/serialize-javascript-7.0.1-before-7.1.3-xss-via-un… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-115754?
- CVE-2026-115754 is a medium-severity vulnerability in Yahoo Serialize-Javascript, classified under Cross-site Scripting. CVSS score: 4.7/10. Published 2026-10-23.
- How severe is CVE-2026-115754?
- Medium severity. CVSS v3 base score is 4.7 out of 10.