Docker Engine before 1.6.1 uses weak permissions for (1) /proc/asound (2) /proc/timer_stats (3) /proc/latency_stats and (4) /proc/fs which allows local users to modify the host obtain sensitive information and perform protocol downgrade attacks via a crafted image.

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CVE-2015-3630: Undefined Security Weakness

Docker Engine before 1.6.1 uses weak permissions for 1 /proc/asound, 2 /proc/timerstats, 3 /proc/latencystats, and 4 /proc/fs, which allows local users to modify the host, obtain sensitive information, and perform protocol downgrade attacks via a crafted image...