SB2021100620 - Debian update for mediawiki



SB2021100620 - Debian update for mediawiki

Published: October 6, 2021

Security Bulletin ID SB2021100620
Severity
Medium
Patch available
YES
Number of vulnerabilities 5
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

Medium 80% Low 20%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 5 secuirty vulnerabilities.


1) Improper access control (CVE-ID: CVE-2021-35197)

The vulnerability allows a remote attacker to gain unauthorized access to otherwise restricted functionality.

The vulnerability exists due to improper access restrictions to purge pages for blocked user accounts. A remote user with a blocked account can purge pages.


2) 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.


3) 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.


4) 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.


5) 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remote user can execute actions, such as global replacement of text in wiki articles even after their permissions have been revoked.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.