IMAP command injection in Roundcube Webmail
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- Low · High · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA.
Summary
Roundcube Webmail from 1.6.0 before 1.6.20 and from 1.7.0 before 1.7.5 is affected. Improper neutralization of CRLF sequences in the _flag parameter of the mail/mark action lets a remote authenticated attacker inject arbitrary IMAP commands (CWE-93).
Written with Claude Haiku 5.5 from the sources below · 2026-11-05
Description from the CNA
Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5 is affected by an IMAP command injection vulnerability. A remote authenticated attacker can exploit this via CRLF sequences injected into the _flag parameter of the mail/mark action to execute arbitrary IMAP commands. Upstream fixed this in the commit “Fix IMAP command injection via CRLF in `_flag` parameter of mail/mark action”, which rejects flags containing control, whitespace and IMAP-special characters.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
Upgrade Roundcube Webmail to 1.6.20 or, on the 1.7 branch, to 1.7.5.
Written with Claude Haiku 5.5 from the sources below · 2026-11-05
- Fix · CNA Webmail (Roundcube) Fixed in 1.6.20, 1.7.5
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Advisory ·
Roundcube Webmail — roundcube.net/news/2026/10/19/security-updates-1.6.20-and-1…
20 records Highest priority Priority LOW 20 LOW
Other records, highest priority first
- TI-2026-79180 Server-side request forgery filter bypass in Roundcube WebmailPriority LOW 38
- TI-2026-79177 Roundcube Webmail passes unsafe SVG and EPS content to ImageMagickPriority LOW 38
- TI-2026-79182 Improper authentication in Roundcube Webmail multi-host alias loginsPriority LOW 37
Vendor assessments
Timeline
- 2026-10-22 Threatist record created from CVE-2026-114720
- 2026-10-22 Alias added: GHSA-3p38-q93v-93w8
- 2026-10-23 Affected versions changed · Red Hat
- 2026-10-23 CVSS score added · Red Hat
- 2026-10-23 Priority changed: MEDIUM → LOW
- 2026-10-26 CISA SSVC decision points changed
References
Patch 4
- https://github.com/roundcube/roundcubemail/commit/6c3c1897c11e193e47fccaabc87e9ca2a0a73e51
- https://github.com/roundcube/roundcubemail/releases/tag/1.7.5
- https://github.com/roundcube/roundcubemail/releases/tag/1.6.20
- https://github.com/roundcube/roundcubemail/commit/242c6d6a150c850bd96d20d400261e71f8d11f9b
More Roundcube Webmail vulnerabilities
- TI-2025-31204 Deserialization of untrusted data in Roundcube Webmail KEVCVSS 3.1CRITICAL 9.9
- TI-2021-19778 Roundcube before 1.3.17 and 1.4.x before 1.4.12 is prone to a potential SQL injection via search or search_params. KEVCVSS 3.1CRITICAL 9.8
- TI-2020-10051 rcube_image.php in Roundcube Webmail before 1.4.4 allows attackers to execute arbitrary… KEVCVSS 3.1CRITICAL 9.8
- TI-2024-28025 A Cross-Site Scripting vulnerability in Roundcube through 1.5.7 and 1.6.x through 1.6.7… KEVCVSS 3.1CRITICAL 9.3
- TI-2017-12250 Roundcube Webmail before 1.1.10, 1.2.x before 1.2.7, and 1.3.x before 1.3.3 allows… KEVCVSS 3.1HIGH 7.8
- TI-2025-41994 Cross-site scripting in Roundcube Webmail KEVCVSS 3.1HIGH 7.2
Sources
- CVE-2026-114720 · CVE Program
- CVE-2026-114720 · NVD
- FIRST EPSS
- GHSA-3p38-q93v-93w8 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-114720 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences