**CRITICAL RISK** CVE-2023-26359 Adobe Coldfusion 2018 / 2021 – Arbitrary Code Execution via Unsafe Deserialization of Untrusted Data

Background & Context

Adobe ColdFusion is a commercial rapid web-application development computing platform (The programming language used with that platform is also commonly called ColdFusion, though is more accurately known as CFML.) ColdFusion was originally designed to make it easier to connect simple HTML pages to a database. By version 2 (1996) it had become a full platform that included an IDE in addition to a full scripting language.

ColdFusion is most often used for data-driven websites or intranets, but can also be used to generate remote services such as REST services, WebSockets, SOAP web services or Flash remoting. It is especially well-suited as the server-side technology to the client-side AJAX.

Vulnerability Summary

Adobe ColdFusion is affected by a Deserialization of Untrusted Data vulnerability. The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid.

It is often convenient to serialize objects for communication or to save them for later use. However, deserialized data or code can often be modified without using the provided accessor functions if it does not use cryptography to protect itself. Furthermore, any cryptography would still be client-side security — which is a dangerous security assumption. Data that is untrusted can not be trusted to be well-formed.


Impact If Exploited

When developers place no restrictions on “gadget chains,” or series of instances and method invocations that can self-execute during the deserialization process (i.e., before the object is returned to the caller), it is sometimes possible for attackers to leverage them to perform unauthorized actions, like generating a shell.

Exploit could result in arbitrary code execution in the context of the current user. Exploitation of this issue does not require user interaction.

NOTE: This vulnerability has been reported by the CISA (America’s Cyber Defense Agency) to be known to be currently actively exploited in the wild as of 22/08/2021.


Affected Product Versions

  • Adobe ColdFusion 2021 Update 5 (and earlier)
  • Adobe ColdFusion 2018 Update 15 (and earlier)


Official Fix & Remediation Guidance

Adobe has released security updates for ColdFusion versions 2021 and 2018. Customers are advised to upgrade to the latest version of Adobe ColdFusion. Updates are available via Adobe’s Security Bulletin, at https://helpx.adobe.com/security/products/coldfusion/apsb23-25.html.

NOTE: Adobe recommends updating your ColdFusion JDK/JRE to the latest version of the LTS releases for JDK 11. Applying the ColdFusion update without a corresponding JDK update will NOT secure the server. See the relevant Tech Notes for more details.

Temporary Mitigation & Workarounds

(The vendor has not advised of any alternative temporary mitigation or workarounds)

NOTE: Caution should always be taken in applying any temporary mitigations listed. Mitigations are only recommended in cases where patches to remediate the vulnerability are not available, or cannot safely be applied to a given environment immediately. A given mitigation may not in all cases be recommended officially by the application vendor. The viability of any given temporary mitigation measure may vary, depending on server platform and existing configuration. Mitigations listed may incompletely remediate any given vulnerability. Configuration changes to implement listed mitigations may impact/disrupt required functionality within a given customer application. Care should therefore be taken to carefully analyse any listed mitigations for appropriateness to a given environment. Customers are advised to test any configuration changes prior to their being introduced into a production environment.


Category: Arbitrary Code Execution



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