CVE-2026-28812 in JSPWiki
Summary
by MITRE • 07/30/2026
UserManager lack of checks allows impersonation in Apache JSPWiki up to 2.12.3 which may allow attackers to escalate privileges. Users are recommended to upgrade to version 2.12.4 or newer which fixes this issue.
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Analysis
by VulDB Data Team • 07/30/2026
The vulnerability in Apache JSPWiki versions prior to 2.12.4 stems from insufficient input validation and access control mechanisms within the UserManager component, creating a critical security flaw that enables unauthorized privilege escalation. This weakness allows malicious actors to exploit the system's authentication and authorization processes, potentially gaining administrative privileges through crafted requests that bypass normal user verification procedures.
The technical implementation flaw occurs when the UserManager component fails to properly validate user credentials and session data during authentication operations. Attackers can manipulate request parameters or session tokens to impersonate legitimate users, particularly those with elevated privileges. This vulnerability directly relates to CWE-287 which addresses improper authentication issues, and represents a significant weakness in the application's access control mechanisms that violates fundamental security principles.
The operational impact of this vulnerability extends beyond simple privilege escalation as it enables attackers to gain full administrative control over JSPWiki instances. Once compromised, attackers can modify or delete wiki content, create malicious pages, manipulate user permissions, and potentially use the compromised system as a foothold for further attacks within the network infrastructure. The vulnerability affects all versions up to 2.12.3, making numerous production environments susceptible to exploitation.
This weakness aligns with several ATT&CK techniques including T1078 Valid Accounts and T1548 Abuse of Functionality, where adversaries leverage legitimate administrative capabilities to maintain persistent access. The vulnerability's exploitation requires minimal technical expertise and can be automated, making it particularly dangerous for organizations running affected versions. Organizations implementing JSPWiki for collaborative documentation or knowledge management systems face significant risk of data compromise and service disruption.
The recommended mitigation strategy involves immediate upgrading to version 2.12.4 or later, which includes proper input validation and enhanced access control checks within the UserManager component. System administrators should also implement additional monitoring and logging of authentication events, review existing user permissions, and consider network segmentation to limit the potential impact of successful exploitation attempts. Security teams should conduct thorough vulnerability assessments across their JSPWiki installations to identify and remediate similar issues in related components.