CyberSecBulletin
CVE-2023-29519NVD status: Modified

xwiki-platform: Improper Neutralization of Special Elements in Output Used by a Downstream Component

CVE-2023-29519 is a high-severity improper neutralization of special elements in output used by a downstream component 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: < 13.10.11; >= 14.0.0, < 14.4.8; >= 14.5.0, < 14.10.2. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.94% chance of exploitation within 30 days, higher than 81% 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 14.4.8 or 14.10.2, 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< 13.10.11; >= 14.0.0, < 14.4.8; >= 14.5.0, < 14.10.2Not stated
XWikiXwikibefore 13.10.11; 14.0 up to, but not including, 14.4.8; 14.5 up to, but not including, 14.10.213.10.11, 14.4.8, 14.10.2

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 3.19.0CriticalCNA (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. A registered user can perform remote code execution leading to privilege escalation by injecting the proper code in the "property" field of an attachment selector, as a gadget of their own dashboard. Note that the vulnerability does not impact comments of a wiki. The vulnerability has been patched in XWiki 13.10.11, 14.4.8, 14.10.2, 15.0-rc-1. Users are advised to upgrade. There are no known workarounds for this vulnerability.

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

The underlying weakness: Improper Neutralization of Special Elements in Output Used by a Downstream Component

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 developers prevent this class of flaw

  • Programming languages and supporting technologies might be chosen which are not subject to these issues.
  • Utilize an appropriate mix of allowlist and denylist parsing to filter control-plane syntax from all input.

More Improper Neutralization of Special Elements in Output Used by a Downstream Component vulnerabilities (CWE-74)

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 Neutralization of Special Elements in Output Used by a Downstream Component vulnerabilities

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