SB2020011633 - Device tracking vulnerability via UDP in Linux kernel

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Main Vulnerability Database SB2020011633

SB2020011633 - Device tracking vulnerability via UDP in Linux kernel

Published: January 16, 2020 Updated: March 9, 2021

Security Bulletin ID SB2020011633
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Information disclosure

Breakdown by Severity

Medium 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Information disclosure (CVE-ID: CVE-2019-18282)

CWE-ID: CWE-200 - Exposure of sensitive information to an unauthorized actor

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green


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.


Remediation

Install update from vendor's website.

References