CyberSecBulletin
CVE-2022-41934NVD status: Modified

xwiki-platform: Improper Encoding or Escaping of Output

CVE-2022-41934 is a high-severity improper encoding or escaping of output vulnerability in xwiki-platform from XWiki, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected xwiki-platform versions: < 13.10.8; >= 14.0.0, < 14.4.3. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.37% chance of exploitation within 30 days, higher than 72% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Xwiki to 13.10.8 or 14.4.3, whichever matches your release line, or a later version.
  2. Read the advisory on github.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
XWikixwiki-platform< 13.10.8; >= 14.0.0, < 14.4.3Not stated
XWikiXwikibefore 13.10.8; 14.0.0 up to, but not including, 14.4.3; 14.4.4; 14.4.513.10.8, 14.4.3

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
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.19.9CriticalCNA (github.com)
CVSS 3.18.8HighNVD

Official description

XWiki Platform is a generic wiki platform offering runtime services for applications built on top of it. Any user with view rights on commonly accessible documents including the menu macro can execute arbitrary Groovy, Python or Velocity code in XWiki leading to full access to the XWiki installation due to improper escaping of the macro content and parameters of the menu macro. The problem has been patched in XWiki 14.6RC1, 13.10.8 and 14.4.3. The patch (commit `2fc20891`) for the document `Menu.MenuMacro` can be manually applied or a XAR archive of a patched version can be imported. The menu macro was basically unchanged since XWiki 11.6 so on XWiki 11.6 or later the patch for version of 13.10.8 (commit `59ccca24a`) can most likely be applied, on XWiki version 14.0 and later the versions in XWiki 14.6 and 14.4.3 should be appropriate.

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

The underlying weakness: 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 developers prevent this class of flaw

  • 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 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.
  • 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.
  • 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.

More Improper Encoding or Escaping of Output vulnerabilities (CWE-116)

Timeline

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

References

Other vulnerabilities in xwiki-platform

All xwiki-platform vulnerabilities

Recent Improper Encoding or Escaping of Output vulnerabilities

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