LiteSpeed Cache Plugin XSS via Comment Attribute Injection

The LiteSpeed Cache WordPress plugin before 7.9.2 does not restrict one of its HTML rewriting routines to stylesheet content, so it removes a quote that terminates an attribute in the rendered page, and combined with unescaped comment author output this allows unauthenticated users whose comment is published to inject attributes that execute JavaScript in the browser of any visitor, including a logged-in administrator, who views front-end pages while the affected option is enabled.

Casky was already ahead

This CVE exploits attack patterns that Casky's 323matched skills already investigate — long before this vulnerability was disclosed. Claude's reasoning model maps these techniques to MITRE ATT&CK, so practitioners who ran these skills have already seen the threat behaviour in their findings.

Analysis

The LiteSpeed Cache WordPress plugin before version 7.9.2 contains a stored cross-site scripting (XSS) vulnerability that exploits improper HTML rewriting logic. The plugin's HTML rewriting routine removes quotes from attribute terminators in rendered pages, and when combined with unescaped comment author output, this allows unauthenticated attackers to inject malicious JavaScript attributes through published comments. Any visitor—including administrators—viewing front-end pages with the affected option enabled becomes vulnerable to executing attacker-controlled JavaScript. This vulnerability is particularly dangerous because it requires no authentication, affects all site visitors including privileged administrators, and persists as stored XSS within published content, making it a high-impact threat to WordPress installations using this popular caching plugin.

Casky's 323 mapped skills enable detection of this attack pattern by correlating MITRE ATT&CK techniques TA0001 (Initial Access) and TA0043 (Reconnaissance) with CWE-79 indicators. Practitioners using Casky would observe detection findings revealing: (1) anomalous HTML attribute structures in comment content where quote termination is missing, indicating the rewriting manipulation; (2) unescaped JavaScript payloads in DOM context within comment author fields; (3) suspicious attribute injection patterns attempting to execute event handlers (onclick, onerror, onload) on visitor browsers. Claude's extended reasoning capability correlates these signals across the plugin's codebase behavior, identifying the chain where comment input bypasses sanitization, flows through the HTML rewriter, and renders executable in visitor sessions—classic indicators of stored XSS exploitation leveraging this specific plugin misconfiguration.

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Casky Risk Score

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EPSS Probability

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Shodan Exposure

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GreyNoise Signal

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Composite risk scoring from EPSS, CISA KEV, Shodan, and GreyNoise — 21 security APIs correlated into a single Casky Risk Score. Coming in Casky Pro. Join early access →

323 Casky skills cover this attack pattern

These skills use Claude AI's reasoning model to surface findings in the same attack categories as CVE-2026-113499.

Abuse of Public-Facing API: Mobile API Abuse

mobile security · low

Run

abusing-dpapi-for-credential-access

red teaming · high

Run

abusing-shadow-credentials-for-privesc

red teaming · high

Run

MITRE ATT&CK Techniques

TA0001 TA0043

Investigate the attack patterns behind CVE-2026-113499

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