Vulnerability identifier: #VU51269
Vulnerability risk: Medium
CVSSv3.1: 4.6 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C]
CVE-ID:
CWE-ID:
CWE-200
Exploitation vector: Network
Exploit availability: No
Vulnerable software:
Linux kernel
Operating systems & Components /
Operating system
Vendor:
Description
The vulnerability allows a remote attacker to track devices via UDP packets.
The vulnerability exists due to excessive data output in the flow_dissector feature in the Linux kernel 4.3 through 5.x before 5.3.10 and affects net/core/flow_dissector.c and
related code. The auto flowlabel of a UDP IPv6 packet relies on a 32-bit hashrnd
value as a secret, and because jhash (instead of siphash) is used. The
hashrnd value remains the same starting from boot time, and can be
inferred by an attacker. A remote attacker can use the
hashrnd value and track reliably track activity of devices using UDP packets.
Mitigation
Install updates from vendor's website.
Vulnerable software versions
External links
http://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.3.10
http://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=55667441c84fa5e0911a0aac44fb059c15ba6da2
http://lists.debian.org/debian-lts-announce/2020/03/msg00001.html
http://security.netapp.com/advisory/ntap-20200204-0002/
http://www.computer.org/csdl/proceedings-article/sp/2020/349700b594/1j2LgrHDR2o
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.