CVE-2026-114724
Description
A flaw was found in Roundcube Webmail. This flaw allows an attacker capable of modifying stored session data to achieve arbitrary code execution through object injection. The vulnerability occurs because session keys prefixed with an exclamation mark are mishandled during session deserialization, desynchronizing the parsed data and allowing subsequent session content to be executed as serialized objects.
Statement
Red Hat has rated this vulnerability as Important because an attacker who successfully injects crafted data into session storage could execute arbitrary code on the host, while the prerequisite of preexisting access to alter backend session records prevents direct, unauthenticated remote exploitation. Roundcube is not shipped in Red Hat Enterprise Linux and is only distributed through community channels such as EPEL. As a result, supported Red Hat enterprise environments are not exposed to this flaw under default installations.
Understanding the Weakness (CWE)
Integrity
Technical Impact: Modify Application Data; Unexpected State
Attackers can modify unexpected objects or data that was assumed to be safe from modification. Deserialized data or code could be modified without using the provided accessor functions, or unexpected functions could be invoked.
Availability
Technical Impact: DoS: Resource Consumption (CPU)
If a function is making an assumption on when to terminate, based on a sentry in a string, it could easily never terminate.
Other
Technical Impact: Varies by Context
The consequences can vary widely, because it depends on which objects or methods are being deserialized, and how they are used. Making an assumption that the code in the deserialized object is valid is dangerous and can enable exploitation. One example is attackers using gadget chains to perform unauthorized actions, such as generating a shell.
Frequently Asked Questions
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