Roundcube Webmail up to 1.6.19/1.7.4 Mail Header rcmail_sendmail References/In-Reply-To/Message-ID/From injection

Summaryinfo

A vulnerability was found in Roundcube Webmail up to 1.6.19/1.7.4. It has been classified as problematic. Affected by this issue is the function rcmail_sendmail of the component Mail Header. The manipulation of the argument References/In-Reply-To/Message-ID/From leads to injection. This vulnerability is traded as CVE-2026-114725. It is possible to initiate the attack remotely. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Roundcube Webmail up to 1.6.19/1.7.4 and classified as problematic. This issue affects the function rcmail_sendmail of the component Mail Header. The manipulation of the argument References/In-Reply-To/Message-ID/From with an unknown input leads to a injection vulnerability. Using CWE to declare the problem leads to CWE-74. The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component. Impacted is integrity. The summary by CVE is:

Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5 is affected by a mail header injection vulnerability. rcmail_sendmail stripped newline characters only from the Subject and Organization headers, leaving other header values taken from request parameters unsanitized, so a remote authenticated attacker could inject arbitrary headers into an outgoing message via the References, In-Reply-To, Message-ID and From parameters. Upstream fixed this in the commit “Fix mail header injection via References/In-Reply-To/Message-ID/From parameters”, which normalizes whitespace in every string header value.

The advisory is shared at bugs.debian.org. The identification of this vulnerability is CVE-2026-114725 since 10/22/2026. The exploitation is known to be easy. The attack may be initiated remotely. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1055 for this issue.

Upgrading to version 1.6.20 or 1.7.5 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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