CyberSecBulletin
CVE-2024-34507NVD status: Modified

mediawiki: Improper Neutralization of Script-Related HTML Tags in a Web Page

Published Updated By the CyberSecBulletin desk

CVE-2024-34507 is a high-severity improper neutralization of script-related HTML tags in a web page vulnerability in mediawiki, with a CVSS 3.1 base score of 7.4 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. There is no confirmed exploitation so far. EPSS estimates a 0.67% chance of exploitation within 30 days, higher than 53% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of mediawiki you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on phabricator.wikimedia.org for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
  4. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
MediaWikimediawikiNot specified in the recordNot stated
Fedora ProjectFedora40Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
RequiredA user must take an action such as opening a file or link.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
HighAll data handled by the component can be read.
Integrity
NoneNothing can be modified.
Availability
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N. Scored by CISA (ADP).

Official description

An issue was discovered in includes/CommentFormatter/CommentParser.php in MediaWiki before 1.39.7, 1.40.x before 1.40.3, and 1.41.x before 1.41.1. XSS can occur because of mishandling of the 0x1b character, as demonstrated by Special:RecentChanges#%1b0000000.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Neutralization of Script-Related HTML Tags in a Web Page

The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special characters such as <, >, and & that could be interpreted as web-scripting elements when they are sent to a downstream component that processes web pages.

How developers prevent this class of flaw

  • With Struts, write all data from form beans with the bean's filter attribute set to true.

More Improper Neutralization of Script-Related HTML Tags in a Web Page vulnerabilities (CWE-80)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Advisories

Other vulnerabilities in mediawiki

All mediawiki vulnerabilities

Recent Improper Neutralization of Script-Related HTML Tags in a Web Page vulnerabilities

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