CVE-2026-103441 Unauthenticated arbitrary file deletion through Wikibase serialized entity parsing
Unauthenticated attackers can execute arbitrary code or delete files via unsafe deserialization in the Wikibase extension.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-103441?
CVE-2026-103441 is a high-severity unsafe deserialization vulnerability in The Wikimedia Foundation MediaWiki Wikibase extension, published on 30 Sep 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
Deserialization of untrusted data vulnerability in The Wikimedia Foundation MediaWiki Wikibase extension allows Leverage Executable Code in Non-Executable Files.
This issue affects MediaWiki Wikibase extension: 1.46, 1.45, and 1.43.
Weakness: CWE-502
Which versions are affected by CVE-2026-103441?
How do I fix CVE-2026-103441?
No fix has been published for CVE-2026-103441 yet. Limit exposure of the affected software until one is available.
Upgrade, and only deserialise data from trusted sources or with an allow-list of types. More about Unsafe deserialization.
Is CVE-2026-103441 being exploited?
There is no known exploitation of CVE-2026-103441 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Sources
Also known as GHSA-5j2p-pvv3-qxhp.