RHEL 6 : rhev-hypervisor6 (RHSA-2014:1354) (Shellshock)
Critical Nessus Plugin ID 79053
SynopsisThe remote Red Hat host is missing a security update.
DescriptionAn updated rhev-hypervisor6 package that fixes several security issues is now available.
Red Hat Product Security has rated this update as having Critical security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.
The rhev-hypervisor6 package provides a Red Hat Enterprise Virtualization Hypervisor ISO disk image. The Red Hat Enterprise Virtualization Hypervisor is a dedicated Kernel-based Virtual Machine (KVM) hypervisor. It includes everything necessary to run and manage virtual machines: a subset of the Red Hat Enterprise Linux operating environment and the Red Hat Enterprise Virtualization Agent.
Note: Red Hat Enterprise Virtualization Hypervisor is only available for the Intel 64 and AMD64 architectures with virtualization extensions.
A flaw was found in the way Bash evaluated certain specially crafted environment variables. An attacker could use this flaw to override or bypass environment restrictions to execute shell commands. Certain services and applications allow remote unauthenticated attackers to provide environment variables, allowing them to exploit this issue.
It was found that the fix for CVE-2014-6271 was incomplete, and Bash still allowed certain characters to be injected into other environments via specially crafted environment variables. An attacker could potentially use this flaw to override or bypass environment restrictions to execute shell commands. Certain services and applications allow remote unauthenticated attackers to provide environment variables, allowing them to exploit this issue.
A flaw was found in the way NSS parsed ASN.1 (Abstract Syntax Notation One) input from certain RSA signatures. A remote attacker could use this flaw to forge RSA certificates by providing a specially crafted signature to an application using NSS. (CVE-2014-1568)
It was discovered that the fixed-sized redir_stack could be forced to overflow in the Bash parser, resulting in memory corruption, and possibly leading to arbitrary code execution when evaluating untrusted input that would not otherwise be run as code. (CVE-2014-7186)
An off-by-one error was discovered in the way Bash was handling deeply nested flow control constructs. Depending on the layout of the .bss segment, this could allow arbitrary execution of code that would not otherwise be executed by Bash. (CVE-2014-7187)
Red Hat would like to thank Stephane Chazelas for reporting CVE-2014-6271, and the Mozilla project for reporting CVE-2014-1568.
Upstream acknowledges Antoine Delignat-Lavaud and Intel Product Security Incident Response Team as the original reporters of CVE-2014-1568. The CVE-2014-7186 and CVE-2014-7187 issues were discovered by Florian Weimer of Red Hat Product Security.
Users of the Red Hat Enterprise Virtualization Hypervisor are advised to upgrade to this updated package.
SolutionUpdate the affected rhev-hypervisor6 package.