CVE-2026-77616
Semantic MediaWiki is a free, open-source extension to MediaWiki that lets users store and query data within the wiki's pages. In versions 7.0.0 through 7.1.0, `Special:Ask` accepts a `cursor` query parameter for keyset pagination (added in 7.0.0). The token is decoded by `CursorEncoder`, which is an **unsigned** base64url-encoded JSON blob, so its contents are fully attacker-controlled.
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When the cursor's sort anchor does not match the request's `sort=` / `order=`, `QueryCreator::applyCursorIfRequested()` builds an error message by interpolating the attacker-controlled `sort_prop` / `sort_order` values into a raw string via `Query::addErrors()`. Unlike SMW's message-key errors, this raw string bypasses the message layer's sanitization (`ProcessingErrorMsgHandler::normalizeAndDecodeMessages()` passes a non-key, non-encoded string through unchanged). `ErrorWidget::queryError()` then assembles the errors and passes them to `Html::errorBox()`, whose first argument is emitted as raw HTML. The result is a reflected cross-site scripting vulnerability: a crafted `cursor` token containing markup in `sort_prop` (or `sort_order`) executes script in the victim's browser on the wiki origin. No authentication or special permission is required. The payload is delivered via a crafted link. Version 7.2.0 contains a fix.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
- Puntuación base: 6.1
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.33%
- Percentil entre todas las CVEs puntuadas: 24
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1189Drive-by Compromiseinitial access95 % - Impacto principal
T1059.007JavaScriptexecution85 %
Reflected XSS en parámetro 'cursor' de Special:Ask sin validación. Vector AV:N/UI:R permite ataque drive-by mediante enlace malicioso que ejecuta JavaScript en el navegador del usuario.
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-79
Referencias
JSON original (NVD)
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"value": "Semantic MediaWiki is a free, open-source extension to MediaWiki that lets users store and query data within the wiki's pages. In versions 7.0.0 through 7.1.0, `Special:Ask` accepts a `cursor` query parameter for keyset pagination (added in 7.0.0). The token is decoded by `CursorEncoder`, which is an **unsigned** base64url-encoded JSON blob, so its contents are fully attacker-controlled. When the cursor's sort anchor does not match the request's `sort=` / `order=`, `QueryCreator::applyCursorIfRequested()` builds an error message by interpolating the attacker-controlled `sort_prop` / `sort_order` values into a raw string via `Query::addErrors()`. Unlike SMW's message-key errors, this raw string bypasses the message layer's sanitization (`ProcessingErrorMsgHandler::normalizeAndDecodeMessages()` passes a non-key, non-encoded string through unchanged). `ErrorWidget::queryError()` then assembles the errors and passes them to `Html::errorBox()`, whose first argument is emitted as raw HTML. The result is a reflected cross-site scripting vulnerability: a crafted `cursor` token containing markup in `sort_prop` (or `sort_order`) executes script in the victim's browser on the wiki origin. No authentication or special permission is required. The payload is delivered via a crafted link. Version 7.2.0 contains a fix."
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"lastModified": "2026-09-24T21:22:19.873",
"sourceIdentifier": "security-advisories@github.com"
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