Is CVE-2026-114731 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-114731 being exploited in the wild.

How severe is CVE-2026-114731?

Medium severity, with a CVSS score of 5.3, published 22 October 2026.

Which products and versions are affected?

Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5.

Is there a fix for CVE-2026-114731?

Yes: fixed in Roundcube Webmail 1.6.20, 1.7.5. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-114731 attacked?

It is attacked over the network, in a web application.

Am I affected by CVE-2026-114731?

Check whether you run Roundcube Webmail at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-114731: Roundcube Webmail uncontrolled resource consumption in CSS proxy

CVE-2026-114731 · Severity: medium · CVSS 5.3 · Published 2026-10-22

Roundcube Webmail is an email client that runs in a web browser. An attacker can force the server to download and store unlimited amounts of data from a malicious CSS stylesheet, exhausting server memory and potentially causing a denial of service. This could render the email service unavailable to legitimate users.

Technologies: Roundcube Webmail. Vendors: Roundcube.

Quick answers

Is CVE-2026-114731 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-114731 being exploited in the wild.
How severe is CVE-2026-114731?: Medium severity, with a CVSS score of 5.3, published 22 October 2026.
Which products and versions are affected?: Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5.
Is there a fix for CVE-2026-114731?: Yes: fixed in Roundcube Webmail 1.6.20, 1.7.5. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-114731 attacked?: It is attacked over the network, in a web application.
Am I affected by CVE-2026-114731?: Check whether you run Roundcube Webmail at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

Fixed in: Roundcube Webmail 1.6.20, 1.7.5

Technical details

The vulnerability is an uncontrolled resource consumption flaw in the CSS proxy (utils/modcss action) that reads stylesheet content into memory without size limits or read timeouts. An attacker can supply a URL to a malicious stylesheet hosted on an attacker-controlled server, causing the Roundcube server to consume unbounded memory. The fix implements a 5 MB size cap, streams the response, and applies a read timeout.

Affected products

Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5

Timeline

2026-10-22: disclosed
2026-10-19: patched

References

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