Package        : ruby-passenger
Version        : 4.0.53-1+deb8u1
CVE ID         : CVE-2015-7519 CVE-2018-12029
Debian Bug     : 864651

Two flaws were discovered in ruby-passenger for Ruby Rails and Rack
support that allowed attackers to spoof HTTP headers or exploit a race
condition which made privilege escalation under certain conditions
possible.

CVE-2015-7519
    Remote attackers could spoof headers passed to applications by using
    an underscore character instead of a dash character in an HTTP
    header as demonstrated by an X_User header.

CVE-2018-12029
    A vulnerability was discovered by the Pulse Security team. It was
    exploitable only when running a non-standard
    passenger_instance_registry_dir, via a race condition where after a
    file was created, there was a window in which it could be replaced
    with a symlink before it was chowned via the path and not the file
    descriptor. If the symlink target was to a file which would be
    executed by root such as root's crontab file, then privilege
    escalation was possible. This is now mitigated by using fchown().

For Debian 8 "Jessie", these problems have been fixed in version
4.0.53-1+deb8u1.

We recommend that you upgrade your ruby-passenger packages.

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