CVE Vulnerabilities

CVE-2022-39298

Deserialization of Untrusted Data

Published: Oct 12, 2022 | Modified: Oct 13, 2022
CVSS 3.x
9.8
CRITICAL
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 2.x
RedHat/V2
RedHat/V3
Ubuntu

MelisFront is the engine that displays website hosted on Melis Platform. It deals with showing pages, plugins, URL rewritting, search optimization and SEO, etc. Attackers can deserialize arbitrary data on affected versions of melisplatform/melis-front, and ultimately leads to the execution of arbitrary PHP code on the system. Conducting this attack does not require authentication. Users should immediately upgrade to melisplatform/melis-front >= 5.0.1. This issue was addressed by restricting allowed classes when deserializing user-controlled data.

Weakness

The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid.

Affected Software

Name Vendor Start Version End Version
Meliscms Melistechnology * 5.0.1 (excluding)

Extended Description

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. 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.

Potential Mitigations

  • Make fields transient to protect them from deserialization.
  • An attempt to serialize and then deserialize a class containing transient fields will result in NULLs where the transient data should be. This is an excellent way to prevent time, environment-based, or sensitive variables from being carried over and used improperly.

References