Debian 9 DLA-2490-1 Critical: x11vnc Information Disclosure Threat

Guenal Davalan reported a flaw in x11vnc, a VNC server to allow remote
access to an existing X session. x11vnc creates shared memory segments
with 0777 mode. A local attacker can take advantage of this flaw for
information disclosure, denial of service or interfering with the VNC
session of another user on the host.


For Debian 9 stretch, this problem has been fixed in version
0.9.13-2+deb9u2.

We recommend that you upgrade your x11vnc packages.

For the detailed security status of x11vnc please refer to
its security tracker page at:
https://security-tracker.debian.org/tracker/source-package/x11vnc

Further information about Debian LTS security advisories, how to apply
these updates to your system and frequently asked questions can be
found at: https://wiki.debian.org/LTS