CVE-2021-42042 Cross-site scripting in n/a
Attackers can inject and execute HTML or JavaScript via unsanitized error messages in the GrowthExperiments extension, potentially compromising user sessions.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2021-42042?
CVE-2021-42042 is a medium-severity cross-site scripting vulnerability in Mediawiki Mediawiki, published on 6 Oct 2021. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.
Official description
An issue was discovered in SpecialEditGrowthConfig in the GrowthExperiments extension in MediaWiki through 1.36.2. The growthexperiments-edit-config-error-invalid-title MediaWiki message was not being properly sanitized and allowed for the injection and execution of HTML and JavaScript.
Weakness: CWE-79
Which versions are affected by CVE-2021-42042?
1 open source package ship an affected version, including mediawiki. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
mediawiki Bitnami | All versions | 1.36.3 |
Products include Mediawiki Mediawiki.
How do I fix CVE-2021-42042?
Upgrade mediawiki to 1.36.3 or later.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2021-42042 being exploited?
There is no known exploitation of CVE-2021-42042 in the wild and no public exploit code.
Other vulnerabilities in Mediawiki Mediawiki
Sources
Also known as BIT-mediawiki-2021-42042, GHSA-4r8j-g46w-hhgp.