Roundcube Webmail before 1.6.21 and 1.7.x before 1.7.6 contains an IMAP command injection vulnerability that allows
Affects roundcubeSource GCVE Database
Not known to be exploited · CVSS 7.4 High.
Data as of 13 Nov 2026, 22:17 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 7.4 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 6.8 |
| CNA | CVSS 4.0 | 7.4 |
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 11 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 13 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10roundcubepkg:deb/ubuntu/roundcube?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu Pro 26.04 LTSroundcubepkg:deb/ubuntu/roundcube?arch=source&distro=esm-apps/resoluteOther threats | Affected
| Fixed in– |
Ubuntu Pro 24.04 LTSroundcubepkg:deb/ubuntu/roundcube?arch=source&distro=esm-apps/nobleOther threats | Affected
| Fixed in– |
Ubuntu Pro 22.04 LTSroundcubepkg:deb/ubuntu/roundcube?arch=source&distro=esm-apps/jammyOther threats | Affected
| Fixed in– |
Ubuntu Pro 20.04 LTSroundcubepkg:deb/ubuntu/roundcube?arch=source&distro=esm-apps/focalOther threats | Affected
| Fixed in– |
Ubuntu Pro 18.04 LTSroundcubepkg:deb/ubuntu/roundcube?arch=source&distro=esm-apps/bionicOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Users should upgrade Roundcube Webmail to version 1.6.21 or later, or 1.7.6 or later, where this vulnerability is fixed. Since the vulnerability requires the messages_cache feature to be enabled, disabling this feature may mitigate risk temporarily if upgrading is not immediately possible.
Description
Roundcube Webmail versions before 1.6.21 and 1.7.x before 1.7.6 contain an IMAP command injection vulnerability. This flaw allows attackers to inject IMAP commands via CRLF sequences in the _uid parameter when the messages_cache feature is enabled. Exploitation requires a logged-in victim to open a crafted GET link, which can result in unauthorized deletion of messages, modification of message flags, or granting mailbox access via SETACL commands.
References
- ubuntu.com/security/CVE-2026-126813 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-126813 (opens in a new tab)
- github.com/roundcube/roundcubemail/blob/1.7.5/program/lib/Roundcube/rcube_imap_generic.php (opens in a new tab)
- github.com/roundcube/roundcubemail/commit/2ea63692178cab5cea486c7c630901b7f6852c80 (opens in a new tab)
- github.com/roundcube/roundcubemail/commit/4cb1cf106b9ca5d465ed4924f2fab5d5108edfeb (opens in a new tab)
- github.com/roundcube/roundcubemail/commit/d1dda13597ceed9df49d434a8d88b758bcf6ef5c (opens in a new tab)
- github.com/roundcube/roundcubemail/releases/tag/1.6.21 (opens in a new tab)
- github.com/roundcube/roundcubemail/releases/tag/1.7.6 (opens in a new tab)
- roundcube.net/news/2026/11/09/security-updates-1.6.21-and-1.7.6 (opens in a new tab)
- vulncheck.com/advisories/roundcube-webmail-before-1.6.21-and-1.7.6-imap-command-injection-via-uid (opens in a new tab)