The flow_dissector feature in the Linux kernel 4.3...
Moderate severity
Unreviewed
Published
May 24, 2022
to the GitHub Advisory Database
•
Updated Jan 29, 2023
Description
Published by the National Vulnerability Database
Jan 16, 2020
Published to the GitHub Advisory Database
May 24, 2022
Last updated
Jan 29, 2023
The flow_dissector feature in the Linux kernel 4.3 through 5.x before 5.3.10 has a device tracking vulnerability, aka CID-55667441c84f. This occurs because the auto flowlabel of a UDP IPv6 packet relies on a 32-bit hashmd value as a secret, and because jhash (instead of siphash) is used. The hashmd value remains the same starting from boot time, and can be inferred by an attacker. This affects net/core/flow_dissector.c and related code.
References