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CVE-2026-39840

Status: AnalyzedMedium (5.1)—

Improper neutralization of input during web page generation ('cross-site scripting') vulnerability in Wikimedia Foundation Mediawiki - Cargo Extension allows XSS Targeting Non-Script Elements.This issue affects Mediawiki - Cargo Extension: before 3.8.7.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (1)

Mediawiki — Cargo

CWEs

References

Raw JSON (NVD)

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  "id": "CVE-2026-39840",
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          "timestamp": "2026-04-07T20:32:58.690563Z"
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  "published": "2026-04-07T20:16:33.923",
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      "url": "https://gerrit.wikimedia.org/r/c/mediawiki/extensions/Cargo/+/1237966",
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    {
      "url": "https://phabricator.wikimedia.org/T416368",
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      "value": "Improper neutralization of input during web page generation ('cross-site scripting') vulnerability in Wikimedia Foundation Mediawiki - Cargo Extension allows XSS Targeting Non-Script Elements.This issue affects Mediawiki - Cargo Extension: before 3.8.7."
    },
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      "value": "Neutralización inadecuada de la entrada durante la generación de páginas web ('cross-site scripting') vulnerabilidad en Wikimedia Foundation Mediawiki - Cargo Extensión permite XSS dirigido a elementos no script. Este problema afecta a Mediawiki - Cargo Extensión: antes de la 3.8.7."
    }
  ],
  "lastModified": "2026-07-24T23:10:00.563",
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