Strategic Overview
- Status
- Patched in 1.7.6
- Affected Plugin
- Browser Screenshots
- Affected Version
< 1.7.6- CVSS
- 5.4Medium
- Weakness type
- CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
- CVE
CVE-2021-24439
At a glance
CVE-2021-24439 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the Browser Screenshots WordPress plugin, affecting versions < 1.7.6. It carries a CVSS score of 5.4 (reachable over the network; low attack complexity). The issue is fixed in version 1.7.6; sites on affected versions should update now. Disclosed June 2021, reported by apple502j.
Vulnerability Overview
The Browser Screenshots WordPress plugin before 1.7.6 allowed authenticated users with a role as low as Contributor to perform Stored Cross-Site Scripting attacks as the image_class parameter of the browser-shot shortcode was not escaped.
Technical Analysis
The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed.
CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Reaching this weakness in Browser Screenshots < 1.7.6 takes a caller who can reach the endpoint. Cross-site scripting happens when input from a request is written into a page without being escaped for the context it lands in, so the browser parses attacker-supplied text as markup or script.
Injected script runs with the privileges of whoever views the affected page, which is how these flaws turn into administrator session theft, silent account creation or persistent backdoors in page content. For Browser Screenshots the fix is 1.7.6: builds < 1.7.6 are affected, anything from 1.7.6 onward is not.
Remediation
Update to version 1.7.6, or a newer patched version
How does WordSec protect against this?
The attempt arrives as an ordinary request to Browser Screenshots: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Browser Screenshots 1.7.6 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