Weglot Plugin Stored XSS via Unescaped URL Rewriting

The Translate WordPress with Weglot 2.0 WordPress plugin before 6.4.3 does not escape the URLs it re-inserts into a page when rewriting links for a translated language, and reverses the encoding that was applied to them beforehand, allowing unauthenticated users to store a payload which executes in the browser of anyone viewing the page in a translated language.

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 Weglot WordPress translation plugin before version 6.4.3 contains a stored cross-site scripting (XSS) vulnerability in its URL rewriting mechanism. When the plugin processes links for translated pages, it fails to properly escape URLs and reverses encoding protections, allowing attackers to inject malicious JavaScript payloads that persist in the page. Any unauthenticated user can exploit this by crafting a specially-encoded URL, and the payload executes whenever site visitors access the translated version. This affects thousands of WordPress sites using Weglot for multilingual content delivery, putting both site administrators and end users at risk of account compromise, credential theft, and malware distribution.

Casky's 323 matching skills leverage Claude's extended reasoning to detect the attack patterns across MITRE techniques TA0001 (Initial Access) and TA0043 (Reconnaissance). Practitioners would identify suspicious findings including: detection of unescaped URL parameters in HTTP responses during translated page requests (CWE-79 signals), encoded payloads being reversed and re-injected into DOM elements, and script execution in translation context handlers. Casky's mapping correlates these indicators to reconnaissance activities where threat actors probe for encoding weaknesses, and initial access vectors where stored payloads activate in victim browsers. The skill set flags the specific pattern of encoding-reversal logic as a high-confidence indicator of this vulnerability class, enabling teams to audit their Weglot implementations and prioritize patching before active exploitation occurs.

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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-2026-88784.

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

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