CVE-2026-75004: Command Injection

Published Aug 17, 2026
·
Updated

In Roundcube Webmail before 1.6.18 and 1.7.x before 1.7.3, improper rule name quoting could lead to managesievedisabledactions setting bypass via a crafted rule name in a Sieve script. This issue only affects Roundcube instances using the managesieve plugin.

Affected Software

2 affected components
Roundcube Roundcube Webmail<1.6.18
Roundcube Roundcube Webmail>1.7.0<1.7.3

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Roundcube Webmail to a version that resolves this vulnerability.

    Fixed in 1.6.18
  2. Upgrade

    Upgrade Roundcube Webmail to a version that resolves this vulnerability.

    Fixed in 1.7.3
  3. Compensating control

    If you cannot immediately upgrade, ensure access to the Roundcube instances that use the managesieve plugin is limited/isolated to trusted users while remediation is in progress.

Event History

Aug 17, 2026
CVE Published
via MITRE·12:53 PM
Data Sourced
via MITRE·12:53 PM
DescriptionSeverityWeakness
Free Weekly Intel

Don't miss critical vulnerabilities

Join thousands of security professionals who receive our weekly digest of trending CVEs, zero-days, and exploited vulnerabilities.

No spam. Unsubscribe anytime.

Frequently Asked Questions

1

What is the severity of CVE-2026-75004?

The severity of CVE-2026-75004 is classified as medium with a score of 4.3.

2

How do I fix CVE-2026-75004?

To fix CVE-2026-75004, upgrade to Roundcube Webmail version 1.6.18 or 1.7.3 or later.

3

What impact does CVE-2026-75004 have on Roundcube Webmail?

CVE-2026-75004 can potentially allow attackers to bypass the managesieve_disabled_actions setting through crafted rule names in Sieve scripts.

4

Which version of Roundcube Webmail is affected by CVE-2026-75004?

CVE-2026-75004 affects Roundcube Webmail versions before 1.6.18 and 1.7.x before 1.7.3.

5

Is the managesieve plugin necessary to be vulnerable to CVE-2026-75004?

Yes, the vulnerability only affects Roundcube instances that are using the managesieve plugin.

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203