CyberSecBulletin
CVE-2023-29209NVD status: Modified

xwiki-platform: Improper Control of Generation of Code

Published Updated By the CyberSecBulletin desk

CVE-2023-29209 is a high-severity improper control of generation of code 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: >= 10.9, < 13.10.11; >= 14.0-rc-1, < 14.4.7; >= 14.5, < 14.10. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.14% chance of exploitation within 30 days, higher than 67% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Xwiki to 13.10.11 or 14.4.7 or 14.10, 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>= 10.9, < 13.10.11; >= 14.0-rc-1, < 14.4.7; >= 14.5, < 14.10Not stated
XWikiXwiki10.9 up to, but not including, 13.10.11; 14.4.0 up to, but not including, 14.4.7; 14.8 up to, but not including, 14.1013.10.11, 14.4.7, 14.10

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 Commons are technical libraries common to several other top level XWiki projects. Any user with view rights on commonly accessible documents including the legacy notification activity macro can execute arbitrary Groovy, Python or Velocity code in XWiki leading to full access to the XWiki installation. The root cause is improper escaping of the macro parameters of the legacy notification activity macro. This macro is installed by default in XWiki. The vulnerability can be exploited via every wiki page that is editable including the user's profile, but also with just view rights using the HTMLConverter that is part of the CKEditor integration which is bundled with XWiki. The vulnerability has been patched in XWiki 13.10.11, 14.4.7 and 14.10.

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

The underlying weakness: Improper Control of Generation of Code

The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.

How developers prevent this class of flaw

  • Refactor your program so that you do not have to dynamically generate code.
  • Run your code in a jail or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which code can be executed by your product. Examples include the Unix chroot jail and AppArmor. In general, managed code may provide some protection. This may not be a feasible solution, and it only limits the impact to the operating system; the rest of your application may still be subject to compromise. Be careful to avoid CWE-243 and other weaknesses related to jails.
  • Use dynamic tools and techniques that interact with the product using large test suites with many diverse inputs, such as fuzz testing (fuzzing), robustness testing, and fault injection. The product's operation may slow down, but it should not become unstable, crash, or generate incorrect results.

More Improper Control of Generation of Code vulnerabilities (CWE-94)

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

Technical write-ups (may include proof of concept)

Other vulnerabilities in xwiki-platform

All xwiki-platform vulnerabilities

Recent Improper Control of Generation of Code vulnerabilities

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