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Friday, December 6th, 2019
| Time |
Event |
| 2:05p |
Security updates for Friday
Security updates have been issued by Debian (libav), Fedora (kernel, libuv, and nodejs), Oracle (firefox), Red Hat (firefox and java-1.7.1-ibm), SUSE (clamav, cloud-init, dnsmasq, dpdk, ffmpeg, munge, opencv, and permissions), and Ubuntu (librabbitmq). | | 2:52p |
VPN hijacking on Linux (and beyond) systems
William Tolley has disclosed a severe VPN-related problem in most current
systems: "I am reporting a vulnerability that exists on most Linux distros, and
other *nix operating systems which allows a network adjacent attacker
to determine if another user is connected to a VPN, the virtual IP
address they have been assigned by the VPN server, and whether or not
there is an active connection to a given website. Additionally, we are
able to determine the exact seq and ack numbers by counting encrypted
packets and/or examining their size. This allows us to inject data into
the TCP stream and hijack connections." There are various partial
mitigations available, but a full solution to the problem has not yet been
worked out. Most VPNs are vulnerable, but Tor evidently is not. | | 6:55p |
[$] Developers split over split-lock detection
A "split lock" is a low-level memory-bus lock taken by the processor for a memory
range that crosses a cache line. Most processors disallow split locks, but
x86 implements them, Split locking may be convenient for developers, but
it comes at a cost: a single split-locked instruction can occupy the memory
bus for around 1,000 clock cycles. It is thus understandable that interest
in eliminating split-lock operations is high. What is perhaps less
understandable is that a patch set intended to detect split locks has been
pending since (at least) May 2018, and it still is not poised to enter the
mainline. |
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