Vladimir Benes discovered an unbounded recursion in the VLAN and TEB Generic Receive Offload (GRO) processing implementations in the Linux kernel, A remote attacker could use this to cause a stack corruption, leading to a denial of service (system crash). It was discovered that a race condition existed in the memory manager of the Linux kernel when handling copy-on-write breakage of private read-only memory mappings. A local attacker could use this to gain administrative privileges.
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Kernel Live Patch Security Notice LSN-0012-1
October 20, 2016
linux vulnerability
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A security issue affects these releases of Ubuntu:
| Series | Base kernel | Arch | flavors |
|------------------+--------------+----------+------------------|
| Ubuntu 16.04 LTS | 4.4.0 | amd64 | generic |
| Ubuntu 16.04 LTS | 4.4.0 | amd64 | lowlatency |
Summary:
Several security issues were fixed in the kernel.
Software Description:
- linux: Linux kernel
Details:
VladimAr BeneA! discovered an unbounded recursion in the VLAN and TEB
Generic Receive Offload (GRO) processing implementations in the Linux
kernel, A remote attacker could use this to cause a stack corruption,
leading to a denial of service (system crash). (CVE-2016-7039, CVE-2016-8666)
It was discovered that a race condition existed in the memory manager of
the Linux kernel when handling copy-on-write breakage of private read-only
memory mappings. A local attacker could use this to gain administrative
privileges. (CVE-2016-5195)
Update instructions:
The problem can be corrected by updating your livepatches to the following
versions:
| Kernel | Version | flavors |
|-----------------+----------+--------------------------|
| 4.4.0-21.37 | 13.3 | generic, lowlatency |
| 4.4.0-22.39 | 13.3 | generic, lowlatency |
| 4.4.0-22.40 | 13.3 | generic, lowlatency |
| 4.4.0-24.43 | 13.3 | generic, lowlatency |
| 4.4.0-28.47 | 13.3 | generic, lowlatency |
| 4.4.0-31.50 | 13.3 | generic, lowlatency |
| 4.4.0-34.53 | 13.3 | generic, lowlatency |
| 4.4.0-36.55 | 13.3 | generic, lowlatency |
| 4.4.0-38.57 | 13.3 | generic, lowlatency |
| 4.4.0-42.62 | 13.3 | generic, lowlatency |
| 4.4.0-43.63 | 13.3 | generic, lowlatency |
Additionally, you should install an updated kernel with these fixes and
reboot at your convienience.
References:
CVE-2016-7039, CVE-2016-8666, CVE-2016-5195