CyberSecBulletin
CVE-2022-42124NVD status: Modified

Digital Experience Platform: Inefficient Regular Expression Complexity

CVE-2022-42124 is a high-severity inefficient regular expression complexity vulnerability in Digital Experience Platform from Liferay, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Digital Experience Platform versions: 7.2; 7.3; 7.4. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.56% chance of exploitation within 30 days, higher than 76% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Liferay Portal to 7.4.3.5 or a later version.
  2. Read the advisory on issues.liferay.com 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.

Affected products and versions

VendorProductAffected versionsFixed in
LiferayDigital Experience Platform7.2; 7.3; 7.4Not stated
LiferayLiferay Portal7.3.2 up to, but not including, 7.4.3.57.4.3.5

Version data comes from NVD's product matching. 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
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

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

Scoring systemScoreSeverityScored by
CVSS 3.17.5HighNVD
CVSS 3.17.5HighCISA (ADP)

Official description

ReDoS vulnerability in LayoutPageTemplateEntryUpgradeProcess in Liferay Portal 7.3.2 through 7.4.3.4 and Liferay DXP 7.2 fix pack 9 through fix pack 18, 7.3 before update 4, and DXP 7.4 GA allows remote attackers to consume an excessive amount of server resources via a crafted payload injected into the 'name' field of a layout prototype.

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

The underlying weakness: Inefficient Regular Expression Complexity

The product uses a regular expression with a worst-case computational complexity that is inefficient and possibly exponential.

How developers prevent this class of flaw

  • Use regular expressions that do not support backtracking, e.g. by removing nested quantifiers.
  • Set backtracking limits in the configuration of the regular expression implementation, such as PHP's pcre.backtrack_limit. Also consider limits on execution time for the process.
  • Do not use regular expressions with untrusted input. If regular expressions must be used, avoid using backtracking in the expression.

More Inefficient Regular Expression Complexity vulnerabilities (CWE-1333)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Digital Experience Platform

All Digital Experience Platform vulnerabilities

Recent Inefficient Regular Expression Complexity vulnerabilities

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