Roundcube Webmail up to 1.6.19/1.7.4 SSRF Filter is_local_url server-side request forgery

Summaryinfo

A vulnerability described as critical has been identified in Roundcube Webmail up to 1.6.19/1.7.4. This vulnerability affects the function rcube_utils::is_local_url of the component SSRF Filter. Executing a manipulation can lead to server-side request forgery. The identification of this vulnerability is CVE-2026-114730. The attack may be launched remotely. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability has been found in Roundcube Webmail up to 1.6.19/1.7.4 and classified as critical. This vulnerability affects the function rcube_utils::is_local_url of the component SSRF Filter. The manipulation with an unknown input leads to a server-side request forgery vulnerability. The CWE definition for the vulnerability is CWE-918. The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

Roundcube Webmail 1.6.14 before 1.6.20 and 1.7.0 before 1.7.5 is affected by a server-side request forgery filter bypass. The network blocklist used by rcube_utils::is_local_url() omitted the RFC 6052 NAT64 prefix 64:ff9b::/96, the RFC 8215 local-use NAT64 prefix 64:ff9b:1::/48 and the unspecified address ::/128, so URLs such as http://[64:ff9b::7f00:1]/ passed the filter and reached loopback, link-local and cloud metadata addresses. Upstream fixed this in the commit “Fix SSRF filter (is_local_url()) bypass via NAT64 64:ff9b::/96”.

The advisory is shared for download at bugs.debian.org. This vulnerability was named CVE-2026-114730 since 10/22/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are known technical details, but no exploit is available.

Upgrading to version 1.6.20 or 1.7.5 eliminates this vulnerability.

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Productinfo

Type

• Mail Client Software

Vendor

• Roundcube

Name

• Webmail

Version

• 1.6.0
• 1.6.1
• 1.6.2
• 1.6.3
• 1.6.4
• 1.6.5
• 1.6.6
• 1.6.7
• 1.6.8
• 1.6.9
• 1.6.10
• 1.6.11
• 1.6.12
• 1.6.13
• 1.6.14
• 1.6.15
• 1.6.16
• 1.6.17
• 1.6.18
• 1.6.19
• 1.7.0
• 1.7.1
• 1.7.2
• 1.7.3
• 1.7.4

License

• free

CPE 2.3info

• 🔒
• 🔒
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CPE 2.2info

• 🔒
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• 🔒

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