Description
The sysrq_sysctl_handler function in kernel/sysctl.c in the Linux kernel before 2.6.39 does not require the CAP_SYS_ADMIN capability to modify the dmesg_restrict value, which allows local users to bypass intended access restrictions and read the kernel ring buffer by leveraging root privileges, as demonstrated by a root user in a Linux Containers (aka LXC) environment.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
n/a n/a
n/aaffected
References
- https://github.com/torvalds/linux/commit/bfdc0b497faa82a0ba2f9dddcf109231dd519fcc ↗
- http://www.openwall.com/lists/oss-security/2011/10/26/10 ↗
- http://ftp.osuosl.org/pub/linux/kernel/v2.6/ChangeLog-2.6.39 ↗
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=bfdc0b497faa82a0ba2f9dddcf109231dd519fcc ↗