Strategic Overview
- Status
- Patched in 3.5.1
- Affected Plugin
- Stars Rating
- Affected Version
< 3.5.1- CVSS
- 7.5High
- Weakness type
- CWE-400 · Uncontrolled Resource Consumption
- CVE
CVE-2021-24893
At a glance
CVE-2021-24893 is a high-severity Uncontrolled Resource Consumption vulnerability in the Stars Rating WordPress plugin, affecting versions < 3.5.1. It carries a CVSS score of 7.5 (reachable over the network; low attack complexity; high availability impact). Exploitation requires no authentication. The issue is fixed in version 3.5.1; sites on affected versions should update now. Disclosed December 2021, reported by Drew Jones.
Vulnerability Overview
The Stars Rating WordPress plugin before 3.5.1 does not validate the submitted rating, allowing submission of long integer, causing a Denial of Service in the comments section, or pending comment dashboard depending if the user sent it as unauthenticated or authenticated.
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. A successful exploit has high impact on availability.
CWE-400: Uncontrolled Resource Consumption
Reaching this weakness in Stars Rating < 3.5.1 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 Stars Rating the fix is 3.5.1: builds < 3.5.1 are affected, anything from 3.5.1 onward is not.
Remediation
Update to version 3.5.1, or a newer patched version
How does WordSec protect against this?
The attempt arrives as an ordinary request to Stars Rating: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Stars Rating 3.5.1 closes this, and updating the plugin is the step that ends it.
- Firewall
- Alerts
External References
Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C