10.0 CVSS RCE via OS command injection in a widely deployed MediaWiki extension; enables full server compromise of internal/external wiki instances and warrants broad notification.
CVE-2026-100382
RCE via OS command injection in MediaWiki ExternalData extension (<3.7).
Is CVE-2026-100382 being exploited?
Not confirmed. CVE-2026-100382 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked.
How severe is CVE-2026-100382?
CVE-2026-100382 is rated Critical with a CVSS score of 10.0. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-100382?
Yes. A fix has been recorded for CVE-2026-100382. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-100382 affect?
CVE-2026-100382 affects MediaWiki ExternalData extension < 3.7, MediaWiki instances using ExternalData extension. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-100382?
Upgrade ExternalData to >=3.7 or remove/disable it; audit and isolate affected hosts.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote code execution on wiki servers via ExternalData input, enabling full system compromise and data exfiltration.
Immediate action required
- affected< 3.7
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.