SB2021100104 - Multiple vulnerabilities in MediaWiki
Published: October 1, 2021
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 4 secuirty vulnerabilities.
1) Stored cross-site scripting (CVE-ID: CVE-2021-41798)
The disclosed vulnerability allows a remote user to perform cross-site scripting (XSS) attacks.
The vulnerability exists due to insufficient sanitization of user-supplied data in Special:Search. A remote user can permanently inject and execute arbitrary HTML and script code in user's browser in context of vulnerable website.
Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.
2) Resource exhaustion (CVE-ID: CVE-2021-41799)
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to application does not properly control consumption of internal resources when processing ApiQueryBacklinks. A remote attacker can trigger resource exhaustion and perform a denial of service (DoS) attack.
3) Improper access control (CVE-ID: CVE-2021-41800)
The vulnerability allows a remote attacker to gain unauthorized access to otherwise restricted functionality.
The vulnerability exists due to improper access restrictions, related to PoolCounter and Special:Contributions section. A remote attacker can bypass implemented security restrictions and gain unauthorized access to the application.
4) Security restrictions bypass (CVE-ID: CVE-2021-41801)
The vulnerability allows a remote attacker to bypass security checks.
The vulnerability exists due to application does not properly check permissions when executing jobs. A remote user can execute actions, such as global replacement of text in wiki articles even after their permissions have been revoked.
Remediation
Install update from vendor's website.