CVE Vulnerabilities

CVE-2016-7050

Deserialization of Untrusted Data

Published: Jun 08, 2017 | Modified: Jun 16, 2017
CVSS 3.x
9.8
CRITICAL
Source:
NVD
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 2.x
7.5 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P
RedHat/V2
6.8 IMPORTANT
AV:N/AC:M/Au:N/C:P/I:P/A:P
RedHat/V3
9 IMPORTANT
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
Ubuntu
MEDIUM

SerializableProvider in RESTEasy in Red Hat Enterprise Linux Desktop 7, Red Hat Enterprise Linux HPC Node 7, Red Hat Enterprise Linux Server 7, and Red Hat Enterprise Linux Workstation 7 allows remote attackers to execute arbitrary code.

Weakness

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

Affected Software

Name Vendor Start Version End Version
Enterprise_linux_desktop Redhat 7.0 (including) 7.0 (including)
Enterprise_linux_hpc_node Redhat 7.0 (including) 7.0 (including)
Enterprise_linux_server Redhat 7.0 (including) 7.0 (including)
Enterprise_linux_workstation Redhat 7.0 (including) 7.0 (including)
Red Hat Enterprise Linux 7 RedHat resteasy-base-0:3.0.6-4.el7 *
Resteasy Ubuntu artful *
Resteasy Ubuntu esm-apps/xenial *
Resteasy Ubuntu xenial *
Resteasy Ubuntu yakkety *
Resteasy Ubuntu zesty *

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