CVE-2014-5265

WordPress Core < 3.9.2 - Denial of Service via XML

2014-08-06 00:00

Strategic Overview

Status: Patched in 3.7.4
Affected Core: WordPress 3.9
Affected Version: 3.7 – 3.9.1 · 4 branches
CVSS: 2.7Low
Weakness type: CWE-400 · Uncontrolled Resource Consumption
CVE: CVE-2014-5265

At a glance

CVE-2014-5265 is a low-severity Uncontrolled Resource Consumption vulnerability in the WordPress 3.9 WordPress release line, affecting 3.7 – 3.9.1 · 4 branches. It carries a CVSS score of 2.7 (reachable over the network; low attack complexity). The issue is fixed in version 3.7.4; sites on affected versions should update now. Disclosed August 2014, reported by Ivan Novikov.

Vulnerability Overview

The Incutio XML-RPC (IXR) Library, as used in WordPress before 3.9.2 and Drupal 6.x before 6.33 and 7.x before 7.31, permits entity declarations without considering recursion during entity expansion, which allows remote attackers to cause a denial of service (memory and CPU consumption) via a crafted XML document containing a large number of nested entity references, a similar issue to CVE-2003-1564.

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 interaction from a victim user.

CWE-400: Uncontrolled Resource Consumption

Reaching this weakness in WordPress 3.9 3.7 – 3.9.1 · 4 branches takes a caller who can reach the endpoint. Uncontrolled resource consumption means a request can make the server do an amount of work it never bounds, because the size or repetition of the job is taken from the request rather than capped by the code.

A single caller can hold PHP workers, database connections or disk open long enough to slow the site for everyone, without needing any account or any other flaw. For WordPress 3.9 the fix is 3.7.4: builds 3.7 – 3.9.1 · 4 branches are affected, anything from 3.7.4 onward is not.

Remediation

Update to one of the following versions, or a newer patched version: 3.7.4, 3.8.4, 3.9.2

How does WordSec protect against this?

The attempt arrives as an ordinary request to WordPress 3.9: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: updating to 3.7.4 is the step that ends it.

Firewall
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2014-5265 https://www.wordfence.com/threat-intel/vulnerabilities/id/4b389604-a999-45a1-a32f-7f8c951cb94c https://nvd.nist.gov/vuln/detail/CVE-2014-5265

Related records

Same weakness class

Other vulnerabilities in WordPress 3.9

CVSS Vector

2.7

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

Base

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

This record contains material that is subject to copyright

CVE Usage: MITRE 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 Common Vulnerabilities and Exposures (CVE®). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy.

https://www.cve.org/Legal/TermsOfUse

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/