CVE-2021-26929
6.1 · MEDIUMOverview
CVE-2021-26929 is a medium-severity vulnerability affecting horde groupware. It was published on February 14, 2021 and has a CVSS 3.1 base score of 6.1 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 6.1, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
An XSS issue was discovered in Horde Groupware Webmail Edition through 5.2.22 (where the Horde_Text_Filter library before 2.3.7 is used). The attacker can send a plain text e-mail message, with JavaScript encoded as a link or email that is mishandled by preProcess in Text2html.php, because bespoke use of \x00\x00\x00 and \x01\x01\x01 interferes with XSS defenses.
Remediation
Check the references section for vendor advisories and patches from horde. Update groupware to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| horde | groupware | 0 | Affected |
References
Frequently Asked Questions
What is CVE-2021-26929?
CVE-2021-26929 is a medium-severity vulnerability affecting horde groupware. It was published on February 14, 2021 and has a CVSS 3.1 base score of 6.1 (MEDIUM).
How severe is CVE-2021-26929?
This vulnerability has a CVSS 3.1 base score of 6.1, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2021-26929?
Check the references section for vendor advisories and patches from horde. Update groupware to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2021-26929?
CyberStrike's AI-powered security agents can automatically detect CVE-2021-26929 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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