Security Advisory Important: qemu-kvm security update

Advisory: RHSA-2011:1801-1
Type: Security Advisory
Severity: Important
Issued on: 2011-12-08
Last updated on: 2011-12-08
Affected Products: Red Hat Enterprise Linux Server EUS (v. 6.1.z)
CVEs ( CVE-2011-4111


Updated qemu-kvm packages that fix one security issue are now available for
Red Hat Enterprise Linux 6.1 Extended Update Support.

The Red Hat Security Response Team has rated this update as having
important security impact. A Common Vulnerability Scoring System (CVSS)
base score, which gives a detailed severity rating, is available from the
CVE link in the References section.

KVM (Kernel-based Virtual Machine) is a full virtualization solution for
Linux on AMD64 and Intel 64 systems. qemu-kvm is the user-space component
for running virtual machines using KVM.

A flaw was found in the way qemu-kvm handled VSC_ATR messages when a guest
was configured for a CCID (Chip/Smart Card Interface Devices) USB smart
card reader in passthrough mode. An attacker able to connect to the port on
the host being used for such a device could use this flaw to crash the
qemu-kvm process on the host or, possibly, escalate their privileges on the
host. (CVE-2011-4111)

All users of qemu-kvm should upgrade to these updated packages, which
contain a backported patch to resolve this issue. After installing this
update, shut down all running virtual machines. Once all virtual machines
have shut down, start them again for this update to take effect.


Before applying this update, make sure all previously-released errata
relevant to your system have been applied.

This update is available via the Red Hat Network. Details on how to
use the Red Hat Network to apply this update are available at

Updated packages

Red Hat Enterprise Linux Server EUS (v. 6.1.z)

qemu-kvm-     MD5: 6f3d43793751bb7f01ae3cae0d1fc338
SHA-256: 904c4b1b124a4668b9dfeadfb248d2c5f1a4dc4ea4ad6809356438bff9324736
qemu-img-     MD5: 3ab76cebb0b33cbb6c42ceb192f88494
SHA-256: f704807a0a056a196a91300887355f2e422e3b5ee5f671c32812648466dab17a
qemu-kvm-     MD5: d27196750820d13dd13db3788b7253f3
SHA-256: 78038f1774e6bf039a3f540c5f616f66ded058d6ef3caf36a350630c1fe507b5
qemu-kvm-debuginfo-     MD5: 92cbf193d9a9db2252acf09886a71770
SHA-256: 626e3a0ee4c996d9c656447e42e19d8c3d9aeed8b2452693b5fedd254f726755
qemu-kvm-tools-     MD5: 8c2d791cf5c00860d236f0b7dc5c9586
SHA-256: 4573150f4ba3ce434b1f4aec4707ee57ec28675c866c5f6ae1da7bb9e61ce800
(The unlinked packages above are only available from the Red Hat Network)

Bugs fixed (see bugzilla for more information)

751310 - CVE-2011-4111 qemu: ccid: buffer overflow in handling of VSC_ATR message


These packages are GPG signed by Red Hat for security. Our key and details on how to verify the signature are available from:

The Red Hat security contact is More contact details at