CVE-2026-74999: In Roundcube Webmail before 1.6.18 and 1.7.x before 1.7.3, the "Add to address book" action was subject to stored XSS

Medium severity · published Aug 17, 2026

CVE-2026-74999

In Roundcube Webmail before 1.6.18 and 1.7.x before 1.7.3, the "Add to address book" action was subject to stored XSS

5.4

CVSS

0.4%

EPSS

On KEV

Description

In Roundcube Webmail before 1.6.18 and 1.7.x before 1.7.3, the "Add to address book" action was subject to stored XSS.

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Attack vector

Network

Complexity

Low

Privileges

Low

User interaction

Required

Confidentiality

Low

Integrity

Low

Availability

None

Scope

Changed

Exploitation

Is it being used?

Exploit prediction (EPSS)0.4% · higher than 30% of CVEs

Exploited in the wildNo evidence yet

CISA KEVNot listed

Ransomware campaign useNot known

Affected products

Which versions

Webmail · Roundcube

1.6.0 before 1.6.18; 1.7.0 before 1.7.3 · source: vendor, NVD

Affected product

Webmail

Roundcube

All Webmail CVEs

References

NVD

https://nvd.nist.gov/vuln/detail/CVE-2026-74999

CVE.org

https://www.cve.org/CVERecord?id=CVE-2026-74999

Patch

https://github.com/roundcube/roundcubemail/commit/2d2a9604a820ee279c9ffcfe856b9b93a93995a8

Patch

https://github.com/roundcube/roundcubemail/commit/32f20c6bfd12dff9cfb6880ae303e740f0804fe8

Release Notes

https://github.com/roundcube/roundcubemail/releases/tag/1.6.18

Release Notes

https://github.com/roundcube/roundcubemail/releases/tag/1.7.3

Vendor Advisory

https://roundcube.net/news/2026/08/09/security-updates-1.6.18-and-1.7.3