Re: CVE-2017-7184: kernel: Local privilege escalation in XFRM framework

[Tyler Hicks <tyhicks () canonical com>]

A PoC is not publicly available for this issue.

Tyler

On 03/29/2017 10:18 PM, Lokesh Ubuntu wrote:
> Is there any POC for this to conclude? Thanks.
>
> Regards, Lokesh
>
> On Mar 30, 2017 03:14, "Tyler Hicks" <tyhicks () canonical com
> <mailto:tyhicks () canonical com>> wrote:
>
>     A security issue was reported by ZDI, on behalf of Chaitin Security
>     Research Lab, against the Linux kernel in Ubuntu. It also affected the
>     upstream kernel.
>
>     Chaitin Security Research Lab discovered that xfrm_replay_verify_len(),
>     as called by xfrm_new_ae(), did not verify that the user-specified
>     replay_window was within the replay state buffer.
>
>     This allowed for out-of-bounds reads and writes of kernel memory.
>     Chaitin Security showed that this can lead to local privilege escalation
>     by using user namespaces in order to configure XFRM. XFRM configuration
>     requires CAP_NET_ADMIN so this issue is mitigated in kernels which do
>     not enable user namespaces by default.
>
>     Fixes:
>     -
>     https://git.kernel.org/linus/677e806da4d916052585301785d847c3b3e6186a 
> <https://git.kernel.org/linus/677e806da4d916052585301785d847c3b3e6186a>
>     -
>     https://git.kernel.org/linus/f843ee6dd019bcece3e74e76ad9df0155655d0df 
> <https://git.kernel.org/linus/f843ee6dd019bcece3e74e76ad9df0155655d0df>
>
>     Tyler

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