GHSA-pfm2-mqwj-ggm5 BIT-mediawiki-2020-10960 CVE-2020-10960
MediaWiki makeCollapsible allows applying event handler to any CSS selector
- Severity
- 5.3 / 10
- Medium · CVSS 3.1
- Exploit chance (EPSS)
- 1.15%
- Chance of exploitation in the next 30 days. Higher than 66.95% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-116 Improper Encoding or Escaping of Output
- CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
- Fix
1.31.7- Upgrade mediawiki/core to this version or later
Description
In MediaWiki before 1.34.1, users can add various Cascading Style Sheets (CSS) classes (which can affect what content is shown or hidden in the user interface) to arbitrary DOM nodes via HTML content within a MediaWiki page. This occurs because jquery.makeCollapsible allows applying an event handler to any Cascading Style Sheets (CSS) selector. There is no known way to exploit this for cross-site scripting (XSS).
Affected versions
Packagist
| Package | Vulnerable | Fixed in |
|---|---|---|
| mediawiki/core | >= 1.31.0, < 1.31.7 |
1.31.7 |
| mediawiki/core | >= 1.33.0, < 1.33.3 |
1.33.3 |
| mediawiki/core | >= 1.34.0, < 1.34.1 |
1.34.1 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
mediawiki/core Packagist → 1.31.7
- composer
composer require mediawiki/core:^1.31.7
Severity breakdown
CVSS 3.1 5.3
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Weakness
CWE-116: Improper Encoding or Escaping of Output
The product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved.
How to prevent it
- Architecture and Design: Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using the ESAPI Encoding control [REF-45] or a similar tool, library, or framework. These will help the programmer encode outputs in a manner less prone to error. Alternately, use built-in functions, but consider using wrappers in case those functions are discovered to have a vulnerability.
- Architecture and Design: If available, use structured mechanisms that automatically enforce the separation between data and code. These mechanisms may be able to provide the relevant quoting, encoding, and validation automatically, instead of relying on the developer to provide this capability at every point where output is generated. For example, stored procedures can enforce database query structure and reduce the likelihood of SQL injection.
- Architecture and Design, Implementation: Understand the context in which your data will be used and the encoding that will be expected. This is especially important when transmitting data between different components, or when generating outputs that can contain multiple encodings at the same time, such as web pages or multi-part mail messages. Study all expected communication protocols and data representations to determine the required encoding strategies.
- Architecture and Design: In some cases, input validation may be an important strategy when output encoding is not a complete solution. For example, you may be providing the same output that will be processed by multiple consumers that use different encodings or representations. In other cases, you may be required to allow user-supplied input to contain control information, such as limited HTML tags that support formatting in a wiki or bulletin board. When this type of requirement must be met, use an extremely strict allowlist to limit which control sequences can be used. Verify that the resulting syntactic structure is what you expect. Use your normal encoding methods for the remainder of the input.
- Architecture and Design: Use input validation as a defense-in-depth measure to reduce the likelihood of output encoding errors (see CWE-20).
- Requirements: Fully specify which encodings are required by components that will be communicating with each other.
- Implementation: When exchanging data between components, ensure that both components are using the same character encoding. Ensure that the proper encoding is applied at each interface. Explicitly set the encoding you are using whenever the protocol allows you to do so.
CWE-74: Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component.
How to prevent it
- Requirements: Programming languages and supporting technologies might be chosen which are not subject to these issues.
- Implementation: Utilize an appropriate mix of allowlist and denylist parsing to filter control-plane syntax from all input.
References
Advisories
Other links
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GHSA-w5fx-cx7f-6vr9 MediaWiki Denial of Service vulnerability | High | Also affects mediawiki/core |
| GHSA-5vj8-g3qg-4qh6 X-Forwarded-For header allows brute-forcing autoblocked IP addresses | Critical | Also affects mediawiki/core |
| GHSA-c8wv-qwwc-6j73 MediaWiki allows a denial of service | Medium | Also affects mediawiki/core |
| GHSA-rqvj-fc2x-99q6 OATHAuth extension in MediaWiki is not implementing rate limit | High | Also affects mediawiki/core |
| GHSA-c4rj-wrmq-52rj MediaWiki Special:UserRights exposes the existence of hidden users | Medium | Also affects mediawiki/core |
| GHSA-h8qx-mj6v-2934 MediaWiki Cross-site Scripting (XSS) vulnerability | Medium | Also affects mediawiki/core |
| GHSA-4vr7-m8p8-434h MediaWiki Cross-site Scripting (XSS) vulnerability | Medium | Also affects mediawiki/core |
| GHSA-2f58-vf6g-6p8x MediaWiki Cross-site Scripting (XSS) vulnerability | Medium | Also affects mediawiki/core |
MergeHarbor checks every repository's dependencies against this database, ranks what matters by exploitability and reachability, routes it to the owning team and opens the fix pull request.
Check your repos with MergeHarbor