Several security issues were fixed in the kernel.
It was discovered that the /proc filesystem did not correctly handle permission changes when programs executed. A local attacker could hold open files to examine details about programs running with higher privileges, potentially increasing the chances of exploiting additional vulnerabilities. (CVE-2011-1020)
9 November 2011
A security issue affects these releases of Ubuntu and its derivatives:
Several security issues were fixed in the kernel.
It was discovered that the /proc filesystem did not correctly handle permission changes when programs executed. A local attacker could hold open files to examine details about programs running with higher privileges, potentially increasing the chances of exploiting additional vulnerabilities. (CVE-2011-1020)
Vasiliy Kulikov discovered that the Bluetooth stack did not correctly clear memory. A local attacker could exploit this to read kernel stack memory, leading to a loss of privacy. (CVE-2011-1078)
Vasiliy Kulikov discovered that the Bluetooth stack did not correctly check that device name strings were NULL terminated. A local attacker could exploit this to crash the system, leading to a denial of service, or leak contents of kernel stack memory, leading to a loss of privacy. (CVE-2011-1079)
Vasiliy Kulikov discovered that bridge network filtering did not check that name fields were NULL terminated. A local attacker could exploit this to leak contents of kernel stack memory, leading to a loss of privacy. (CVE-2011-1080)
Johan Hovold discovered that the DCCP network stack did not correctly handle certain packet combinations. A remote attacker could send specially crafted network traffic that would crash the system, leading to a denial of service. (CVE-2011-1093)
Peter Huewe discovered that the TPM device did not correctly initialize memory. A local attacker could exploit this to read kernel heap memory contents, leading to a loss of privacy. (CVE-2011-1160)
Dan Rosenberg discovered that the IRDA subsystem did not correctly check certain field sizes. If a system was using IRDA, a remote attacker could send specially crafted traffic to crash the system or gain root privileges. (CVE-2011-1180)
Ryan Sweat discovered that the GRO code did not correctly validate memory. In some configurations on systems using VLANs, a remote attacker could send specially crafted traffic to crash the system, leading to a denial of service. (CVE-2011-1478)
It was discovered that the security fix for CVE-2010-4250 introduced a regression. A remote attacker could exploit this to crash the system, leading to a denial of service. (CVE-2011-1479)
Dan Rosenberg discovered that the X.25 Rose network stack did not correctly handle certain fields. If a system was running with Rose enabled, a remote attacker could send specially crafted traffic to gain root privileges. (CVE-2011-1493)
It was discovered that the Stream Control Transmission Protocol (SCTP) implementation incorrectly calculated lengths. If the net.sctp.addip_enable variable was turned on, a remote attacker could send specially crafted traffic to crash the system. (CVE-2011-1573)
Ryan Sweat discovered that the kernel incorrectly handled certain VLAN packets. On some systems, a remote attacker could send specially crafted traffic to crash the system, leading to a denial of service. (CVE-2011-1576)
Timo Warns discovered that the GUID partition parsing routines did not correctly validate certain structures. A local attacker with physical access could plug in a specially crafted block device to crash the system, leading to a denial of service. (CVE-2011-1577)
Phil Oester discovered that the network bonding system did not correctly handle large queues. On some systems, a remote attacker could send specially crafted traffic to crash the system, leading to a denial of service. (CVE-2011-1581)
It was discovered that CIFS incorrectly handled authentication. When a user had a CIFS share mounted that required authentication, a local user could mount the same share without knowing the correct password. (CVE-2011-1585)
It was discovered that the GRE protocol incorrectly handled netns initialization. A remote attacker could send a packet while the ip_gre module was loading, and crash the system, leading to a denial of service. (CVE-2011-1767)
It was discovered that the IP/IP protocol incorrectly handled netns initialization. A remote attacker could send a packet while the ipip module was loading, and crash the system, leading to a denial of service. (CVE-2011-1768)
Ben Greear discovered that CIFS did not correctly handle direct I/O. A local attacker with access to a CIFS partition could exploit this to crash the system, leading to a denial of service. (CVE-2011-1771)
Timo Warns discovered that the EFI GUID partition table was not correctly parsed. A physically local attacker that could insert mountable devices could exploit this to crash the system or possibly gain root privileges. (CVE-2011-1776)
Vasiliy Kulikov and Dan Rosenberg discovered that ecryptfs did not correctly check the origin of mount points. A local attacker could exploit this to trick the system into unmounting arbitrary mount points, leading to a denial of service. (CVE-2011-1833)
Ben Hutchings reported a flaw in the kernel’s handling of corrupt LDM partitions. A local user could exploit this to cause a denial of service or escalate privileges. (CVE-2011-2182)
Dan Rosenberg discovered that the IPv4 diagnostic routines did not correctly validate certain requests. A local attacker could exploit this to consume CPU resources, leading to a denial of service. (CVE-2011-2213)
It was discovered that an mmap() call with the MAP_PRIVATE flag on “/dev/zero” was incorrectly handled. A local attacker could exploit this to crash the system, leading to a denial of service. (CVE-2011-2479)
Vasiliy Kulikov discovered that taskstats listeners were not correctly handled. A local attacker could expoit this to exhaust memory and CPU resources, leading to a denial of service. (CVE-2011-2484)
It was discovered that Bluetooth l2cap and rfcomm did not correctly initialize structures. A local attacker could exploit this to read portions of the kernel stack, leading to a loss of privacy. (CVE-2011-2492)
Sami Liedes discovered that ext4 did not correctly handle missing root inodes. A local attacker could trigger the mount of a specially crafted filesystem to cause the system to crash, leading to a denial of service. (CVE-2011-2493)
Robert Swiecki discovered that mapping extensions were incorrectly handled. A local attacker could exploit this to crash the system, leading to a denial of service. (CVE-2011-2496)
Dan Rosenberg discovered that the Bluetooth stack incorrectly handled certain L2CAP requests. If a system was using Bluetooth, a remote attacker could send specially crafted traffic to crash the system or gain root privileges. (CVE-2011-2497)
Ben Pfaff discovered that Classless Queuing Disciplines (qdiscs) were being incorrectly handled. A local attacker could exploit this to crash the system, leading to a denial of service. (CVE-2011-2525)
It was discovered that GFS2 did not correctly check block sizes. A local attacker could exploit this to crash the system, leading to a denial of service. (CVE-2011-2689)
It was discovered that the EXT4 filesystem contained multiple off-by-one flaws. A local attacker could exploit this to crash the system, leading to a denial of service. (CVE-2011-2695)
Fernando Gont discovered that the IPv6 stack used predictable fragment identification numbers. A remote attacker could exploit this to exhaust network resources, leading to a denial of service. (CVE-2011-2699)
Mauro Carvalho Chehab discovered that the si4713 radio driver did not correctly check the length of memory copies. If this hardware was available, a local attacker could exploit this to crash the system or gain root privileges. (CVE-2011-2700)
Herbert Xu discovered that certain fields were incorrectly handled when Generic Receive Offload (CVE-2011-2723)
The performance counter subsystem did not correctly handle certain counters. A local attacker could exploit this to crash the system, leading to a denial of service. (CVE-2011-2918)
Time Warns discovered that long symlinks were incorrectly handled on Be filesystems. A local attacker could exploit this with a malformed Be filesystem and crash the system, leading to a denial of service. (CVE-2011-2928)
Qianfeng Zhang discovered that the bridge networking interface incorrectly handled certain network packets. A remote attacker could exploit this to crash the system, leading to a denial of service. (CVE-2011-2942)
Dan Kaminsky discovered that the kernel incorrectly handled random sequence number generation. An attacker could use this flaw to possibly predict sequence numbers and inject packets. (CVE-2011-3188)
Darren Lavender discovered that the CIFS client incorrectly handled certain large values. A remote attacker with a malicious server could exploit this to crash the system or possibly execute arbitrary code as the root user. (CVE-2011-3191)
Yasuaki Ishimatsu discovered a flaw in the kernel’s clock implementation. A local unprivileged attacker could exploit this causing a denial of service. (CVE-2011-3209)
Yogesh Sharma discovered that CIFS did not correctly handle UNCs that had no prefixpaths. A local attacker with access to a CIFS partition could exploit this to crash the system, leading to a denial of service. (CVE-2011-3363)
A flaw was discovered in the Linux kernel’s AppArmor security interface when invalid information was written to it. An unprivileged local user could use this to cause a denial of service on the system. (CVE-2011-3619)
A flaw was found in the Linux kernel’s /proc/*/map interface. A local, unprivileged user could exploit this flaw to cause a denial of service. (CVE-2011-3637)
Scot Doyle discovered that the bridge networking interface incorrectly handled certain network packets. A remote attacker could exploit this to crash the system, leading to a denial of service. (CVE-2011-4087)
A bug was found in the way headroom check was performed in udp6_ufo_fragment() function. A remote attacker could use this flaw to crash the system. (CVE-2011-4326)
Ben Hutchings discovered several flaws in the Linux Rose (X.25 PLP) layer. A local user or a remote user on an X.25 network could exploit these flaws to execute arbitrary code as root. (CVE-2011-4914)
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
After a standard system update you need to reboot your computer to make all the necessary changes.
ATTENTION: Due to an unavoidable ABI change the kernel updates have been given a new version number, which requires you to recompile and reinstall all third party kernel modules you might have installed. If you use linux-restricted-modules, you have to update that package as well to get modules which work with the new kernel version. Unless you manually uninstalled the standard kernel metapackages (e.g. linux-generic, linux-server, linux-powerpc), a standard system upgrade will automatically perform this as well.
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