Is CVE-2026-103446 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-103446 being exploited in the wild.

How severe is CVE-2026-103446?

Informational severity, published 30 September 2026.

Which products and versions are affected?

Wikimedia Foundation MediaWiki WikiLambda 1.46.

Is there a fix for CVE-2026-103446?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-103446 attacked?

It is attacked over the network, in a web application.

Am I affected by CVE-2026-103446?

Check whether you run Wikimedia Foundation MediaWiki WikiLambda at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-103446: MediaWiki WikiLambda authorization bypass in abstract fragment execution

CVE-2026-103446 · Severity: info · Published 2026-09-30

The MediaWiki WikiLambda extension allows anonymous users to submit arbitrary code fragments to be executed by the WikiLambda evaluator service, bypassing intended permission checks. An attacker can exploit this to execute native code in the sandboxed evaluator without authentication or authorization, potentially gaining access to the evaluator's capabilities and data.

Vendors: Wikimedia Foundation.

Quick answers

Is CVE-2026-103446 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-103446 being exploited in the wild.
How severe is CVE-2026-103446?: Informational severity, published 30 September 2026.
Which products and versions are affected?: Wikimedia Foundation MediaWiki WikiLambda 1.46.
Is there a fix for CVE-2026-103446?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-103446 attacked?: It is attacked over the network, in a web application.
Am I affected by CVE-2026-103446?: Check whether you run Wikimedia Foundation MediaWiki WikiLambda at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The abstractwiki_run_fragment API accepts caller-supplied fragment data and forwards it to the WikiLambda evaluator service without checking the wikilambda-abstract-run-unsaved-fragment permission, whereas the sibling abstractwiki_fetch_section API properly enforces this check. Anonymous users can submit fragments containing native code implementations, bypassing the authorization boundary that protects unsaved Abstract Wikipedia fragments. The vulnerability requires WikiLambda to be installed with Abstract Wikipedia mode enabled and a configured evaluator endpoint.

Affected products

Wikimedia Foundation MediaWiki WikiLambda 1.46

Timeline

2026-08-17: disclosed
2026-09-30: other: CVE published

References

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