WordPress Core 4.7.0-6.3.1 - Denial of Service via Cache Poisoning

2023-10-12 00:00

Strategic Overview

Status: Patched in 4.7.27
Affected Core: WordPress 6.3
Affected Version: 4.7 – 6.3.1 · 17 branches
CVSS: 5.3Medium
Weakness type: CWE-1250 · Improper Preservation of Consistency Between Independent Representations of Shared State
CVE: CVE pending

At a glance

This record tracks a medium-severity Improper Preservation of Consistency Between Independent Representations of Shared State vulnerability in the WordPress 6.3 WordPress release line, affecting 4.7 – 6.3.1 · 17 branches. It carries a CVSS score of 5.3 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 4.7.27; sites on affected versions should update now. Disclosed October 2023, reported by s5s.

Vulnerability Overview

WordPress Core is vulnerable to Denial of Service via Cache Poisoning in versions between 4.7.0 and 6.3.1. In cases where the X-HTTP-Method-Override header was sent in a request to a REST endpoint and the endpoint returned a 4xx error, the error could be cached, resulting in denial of service.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user.

CWE-1250: Improper Preservation of Consistency Between Independent Representations of Shared State

The product has or supports multiple distributed components or sub-systems that are each required to keep their own local copy of shared data - such as state or cache - but the product does not ensure that all local copies remain consistent with each other.

Remediation

Update to one of the following versions, or a newer patched version: 4.7.27, 4.8.23, 4.9.24, 5.0.20, 5.1.17, 5.2.19, 5.3.16, 5.4.14, 5.5.13, 5.6.12, 5.7.10, 5.8.8, 5.9.8, 6.0.6, 6.1.4, 6.2.3, 6.3.2

How does WordSec protect against this?

The fix is the thing that ends this: updating to 4.7.27 is the step that ends it.

Alerts

External References

https://www.wordfence.com/threat-intel/vulnerabilities/id/bdc84664-2a04-4cc6-ac3f-48bfd432691f

Related records

Other vulnerabilities in WordPress 6.3

CVSS Vector

5.3

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged
ConfidentialityNone
IntegrityNone
AvailabilityLow

This record contains material that is subject to copyright

Defiant hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute this software vulnerability information. Any copy of the software vulnerability information you make for such purposes is authorized provided that you include a hyperlink to this vulnerability record and reproduce Defiant's copyright designation and this license in any such copy.

https://www.wordfence.com/wordfence-intelligence-terms-and-conditions/