CVE-2026-109990 json
Flying Scripts: Delay JavaScript to Improve Site Speed & Performance <= 1.2.4 - Unauthenticated Stored Cross-Site Scripting via Comment Content
published 24d ago modified 24d ago also EUVD-2026-102612
- cvss
- 7.2
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 26%
- public exploits
- 0
- none known
Summary
The Flying Scripts: Delay JavaScript to Improve Site Speed & Performance plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'comment' parameter in all versions up to, and including, 1.2.4 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The exploit bypasses WordPress core's save-time kses sanitization entirely because the payload uses only kses-allowed elements — an <abbr title> attribute and <code> text content — and the XSS is introduced post-save when the plugin's output-buffer rewriter substitutes a double-quote-bearing <code> body into the <abbr title> attribute via predictable, unsalted ___noise___ placeholder keys.
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 24d ago
Exploit prediction
0.33% chance of exploitation in the next 30 days, higher than 26% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N |
Affected products
- gijo Flying Scripts: Delay JavaScript to Improve Site Speed & Performance
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/0ddc518c-02a0-46a5-93e9-0d92a045b35b?source=cve
- plugins.trac.wordpress.org /browser/flying-scripts/tags/1.2.4/html-rewrite.php#L36
- plugins.trac.wordpress.org /browser/flying-scripts/tags/1.2.4/html-rewrite.php#L64
- plugins.trac.wordpress.org /browser/flying-scripts/tags/1.2.4/lib/dom-parser.php#L2207
- plugins.trac.wordpress.org /browser/flying-scripts/tags/1.2.4/lib/dom-parser.php#L2112
- plugins.trac.wordpress.org /browser/flying-scripts/tags/1.2.4/lib/dom-parser.php#L2226
- plugins.trac.wordpress.org /browser/flying-scripts/tags/1.2.4/lib/dom-parser.php#L497
- plugins.trac.wordpress.org /changeset?reponame=&old=3737597%40flying-scripts&new=3737597%40flying-scripts
Sources
- CVE List CVE-2026-109990
- NVD CVE-2026-109990
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