This vulnerability involves the display of autoblocked IP addresses within the tools sidebar of MediaWiki, which leaks sensitive information to users who can view the page. The flaw originates in files under includes/Skin/Skin.php. Attackers or unauthenticated users can gain knowledge of IP addresses that the system automatically blocks, potentially exposing patterns of block activity or personal identifiers.

MediaWiki versions prior to 1.43.7, 1.44.4, or 1.45.2 are affected. Administrators running any of these releases should consider applying the fix in later patches.

The CVSS score of 2.1 indicates a low impact. Because the EPSS score is unavailable and the vulnerability is not listed in the CISA KEV catalog, the practical likelihood of exploitation is uncertain but the information leakage could still be valuable to a determined attacker. The flaw appears to be exploitable by any user who can access the tools sidebar, either locally or remotely through normal browsing, suggesting that privileged access is not required. Mitigation mainly involves applying the vendor's patch or upgrading to a non-affected release.