Medium severity · published Feb 14, 2021
CVE-2021-26929
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)
6.1
CVSS
4.9%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)4.9% · higher than 92% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
9.0 · source: NVD
GR
Groupware · Horde
through 5.2.22 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-26929
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-26929
Exploit
http://packetstormsecurity.com/files/162187/Webmail-Edition-5.2.22-XSS-Remote-Code-Execution.html
Third Party Advisory
http://packetstormsecurity.com/files/162194/Horde-Groupware-Webmail-5.2.22-Cross-Site-Scripting.html
Third Party Advisory
https://github.com/horde/webmail/releases
Mailing List
https://lists.debian.org/debian-lts-announce/2021/02/msg00028.html
Mailing List
https://lists.horde.org/archives/announce/2021/001298.html
Exploit
https://www.alexbirnberg.com/horde-xss.html
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