CVE-2023-50723: 
Java vulnerability analysis and mitigation

CVE-2023-50723 affects XWiki Platform, a generic wiki platform, from version 2.3 up to versions 14.10.15, 15.5.2, and 15.7-rc-1. The vulnerability allows any user who can edit a wiki page to gain programming rights through several cases of missing escaping in the code for displaying sections in the administration interface. The issue was discovered in July 2023 and fixed in December 2023 with the release of XWiki versions 14.10.15, 15.5.2, and 15.7RC1 (GitHub Advisory).

The vulnerability stems from insufficient escaping in the administration interface code, particularly in the ConfigurableClass and ConfigurableClassMacros components. It allows code injection through multiple vectors including configuration section headings, document references, and class names. The vulnerability has received a CVSS v3.1 base score of 9.9 CRITICAL (AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H) from GitHub, and 8.8 HIGH from NVD. The weakness is classified as CWE-94 (Improper Control of Generation of Code) and CWE-95 (Improper Neutralization of Directives in Dynamically Evaluated Code) (NVD).

The vulnerability impacts the confidentiality, integrity, and availability of the entire XWiki installation. Since all users are typically allowed to edit their own user profiles, this vulnerability is potentially exploitable by any authenticated user of the XWiki instance. Successful exploitation allows attackers to execute arbitrary code with elevated privileges, effectively gaining programming rights within the system (GitHub Advisory).

The vulnerability has been fixed in XWiki versions 14.10.15, 15.5.2, and 15.7RC1. For users unable to upgrade immediately, manual workarounds are available by applying patches to two specific pages: XWiki.ConfigurableClassMacros and XWiki.ConfigurableClass. The patches involve improving escaping of configuration section headings and error messages. Additionally, changing the XWiki.ConfigurableClass page to xwiki/2.1 syntax is recommended for proper escaping functionality (GitHub Advisory).