ALAS-2011-016


Amazon Linux AMI Security Advisory: ALAS-2011-16
Advisory Release Date: 2014-09-14 14:40 Pacific
Severity: Medium

Issue Overview:

The skb_gro_header_slow function in include/linux/netdevice.h in the Linux kernel before 2.6.39.4, when Generic Receive Offload (GRO) is enabled, resets certain fields in incorrect situations, which allows remote attackers to cause a denial of service (system crash) via crafted network traffic.

Race condition in the ecryptfs_mount function in fs/ecryptfs/main.c in the eCryptfs subsystem in the Linux kernel before 3.1 allows local users to bypass intended file permissions via a mount.ecryptfs_private mount with a mismatched uid.

The (1) IPv4 and (2) IPv6 implementations in the Linux kernel before 3.1 use a modified MD4 algorithm to generate sequence numbers and Fragment Identification values, which makes it easier for remote attackers to cause a denial of service (disrupted networking) or hijack network sessions by predicting these values and sending crafted packets.

Integer signedness error in the CIFSFindNext function in fs/cifs/cifssmb.c in the Linux kernel before 3.1 allows remote CIFS servers to cause a denial of service (memory corruption) or possibly have unspecified other impact via a large length value in a response to a read request for a directory.

The Performance Events subsystem in the Linux kernel before 3.1 does not properly handle event overflows associated with PERF_COUNT_SW_CPU_CLOCK events, which allows local users to cause a denial of service (system hang) via a crafted application.


Affected Packages:

kernel


Issue Correction:
Run yum update kernel to update your system. You will need to reboot your system in order for the new kernel to be running.

New Packages:
i686:
    perf-2.6.35.14-97.44.amzn1.i686
    kernel-debuginfo-2.6.35.14-97.44.amzn1.i686
    kernel-debuginfo-common-i686-2.6.35.14-97.44.amzn1.i686
    kernel-headers-2.6.35.14-97.44.amzn1.i686
    kernel-2.6.35.14-97.44.amzn1.i686
    kernel-devel-2.6.35.14-97.44.amzn1.i686

noarch:
    kernel-doc-2.6.35.14-97.44.amzn1.noarch

src:
    kernel-2.6.35.14-97.44.amzn1.src

x86_64:
    kernel-2.6.35.14-97.44.amzn1.x86_64
    kernel-debuginfo-2.6.35.14-97.44.amzn1.x86_64
    kernel-headers-2.6.35.14-97.44.amzn1.x86_64
    kernel-debuginfo-common-x86_64-2.6.35.14-97.44.amzn1.x86_64
    perf-2.6.35.14-97.44.amzn1.x86_64
    kernel-devel-2.6.35.14-97.44.amzn1.x86_64