Name: CVE-2021-26929: Improper Neutralization of Input During Web Page Generation
Creator: Rapid7
Published: 2021-02-14T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2021-26929, CWE-79, CVSS 6.1, EPSS 0.04944

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.

CVSS Details

CVSS 3.1 Base Score: 6.1
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Debian	—	Upgrade php-horde-text-filter	Feb 22, 2021	Feb 14, 2021
Ubuntu	—	No solution exists	Jun 26, 2025	Feb 14, 2021

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CVSS Details

Covered by Rapid7

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