Stored cross-site scripting in Flying Scripts WordPress plugin
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Cross-site scripting
- Confidentiality · integrity · availability
- Low · Low · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-79.
Summary
The Flying Scripts: Delay JavaScript to Improve Site Speed & Performance plugin for WordPress by gijo, in all versions through 1.2.4, does not properly sanitize and escape the comment parameter (CWE-79). An unauthenticated attacker can store arbitrary web scripts in pages that run in the browser of any user who opens an injected page.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
Description from the CNA
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
The sources list no fixed version for Flying Scripts: Delay JavaScript to Improve Site Speed & Performance.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
Timeline
- 2026-10-16 Threatist record created from CVE-2026-109990
- 2026-10-16 CISA SSVC decision points changed
- 2026-10-16 Priority changed: MEDIUM → LOW
- 2026-10-16 Alias added: GHSA-x96v-mfm7-f4rv
References
Other 8
- https://www.wordfence.com/threat-intel/vulnerabilities/id/0ddc518c-02a0-46a5-93e9-0d92a045b35b?source=cve
- https://plugins.trac.wordpress.org/browser/flying-scripts/tags/1.2.4/html-rewrite.php#L36
- https://plugins.trac.wordpress.org/browser/flying-scripts/tags/1.2.4/html-rewrite.php#L64
- https://plugins.trac.wordpress.org/browser/flying-scripts/tags/1.2.4/lib/dom-parser.php#L2207
- https://plugins.trac.wordpress.org/browser/flying-scripts/tags/1.2.4/lib/dom-parser.php#L2112
- https://plugins.trac.wordpress.org/browser/flying-scripts/tags/1.2.4/lib/dom-parser.php#L2226
- https://plugins.trac.wordpress.org/browser/flying-scripts/tags/1.2.4/lib/dom-parser.php#L497
- https://plugins.trac.wordpress.org/changeset?reponame=&old=3737597%40flying-scripts&new=3737597%40flying-scripts
More gijo vulnerabilities
- TI-2026-86174 Stored cross-site scripting in Flying Images WordPress plugin CVSS 3.1HIGH 7.2
- TI-2025-10936 Cross-site scripting in gijo Flying Images: Optimize and Lazy Load Images for Faster Page… CVSS 3.1MEDIUM 4.4
Sources
- CVE-2026-109990 · CVE Program
- CVE-2026-109990 · NVD
- FIRST EPSS
- GHSA-x96v-mfm7-f4rv · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences