Vulnerability identifier: #VU38653
Vulnerability risk: Medium
CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N/E:U/RL:O/RC:C]
CVE-ID:
CWE-ID:
CWE-20
Exploitation vector: Network
Exploit availability: No
Vulnerable software:
Tor
Client/Desktop applications /
Web browsers
Vendor: tor.eff.org
Description
The vulnerability allows a remote non-authenticated attacker to manipulate data.
debian/tor.init in the Debian tor_0.2.9.11-1~deb9u1 package for Tor was designed to execute aa-exec from the standard system pathname if the apparmor package is installed, but implements this incorrectly (with a wrong assumption that the specific pathname would remain the same forever), which allows attackers to bypass intended AppArmor restrictions by leveraging the silent loss of this protection mechanism. NOTE: this does not affect systems, such as default Debian stretch installations, on which Tor startup relies on a systemd unit file (instead of this tor.init script).
Mitigation
Install update from vendor's website.
Vulnerable software versions
Tor: 0.2.9.11-1
External links
http://www.securityfocus.com/bid/99933
http://bugs.debian.org/869153
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.