CVE-2020-7451: Medium severity freebsd kernel vulnerability

Published Apr 28, 2020

Updated

In FreeBSD 12.1-STABLE before r358739, 12.1-RELEASE before 12.1-RELEASE-p3, 11.3-STABLE before r358740, and 11.3-RELEASE before 11.3-RELEASE-p7, a TCP SYN-ACK or challenge TCP-ACK segment over IPv6 that is transmitted or retransmitted does not properly initialize the Traffic Class field disclosing one byte of kernel memory over the network.

Affected Software

10 affected components

FreeBSD FreeBSD=11.3

FreeBSD FreeBSD=11.3-p1

FreeBSD FreeBSD=11.3-p2

FreeBSD FreeBSD=11.3-p3

FreeBSD FreeBSD=11.3-p4

FreeBSD FreeBSD=11.3-p5

FreeBSD FreeBSD=11.3-p6

FreeBSD FreeBSD=12.1

FreeBSD FreeBSD=12.1-p1

FreeBSD FreeBSD=12.1-p2

Remediation

Patch Available

https://security.FreeBSD.org/advisories/FreeBSD-SA-20:04.tcp.asc

Event History

Apr 28, 2020

CVE Published

via MITRE·07:11 PM

Data Sourced

via MITRE·07:11 PM

DescriptionWeakness

Frequently Asked Questions

What is CVE-2020-7451?

CVE-2020-7451 is a vulnerability in FreeBSD that allows an attacker to disclose information from the Traffic Class field of a TCP SYN-ACK or challenge TCP-ACK segment over IPv6.

What versions of FreeBSD are affected by CVE-2020-7451?

FreeBSD 12.1-STABLE before r358739, 12.1-RELEASE before 12.1-RELEASE-p3, 11.3-STABLE before r358740, and 11.3-RELEASE before 11.3-RELEASE-p7 are affected.

How severe is CVE-2020-7451?

CVE-2020-7451 has a severity score of 5.3 (Medium).

How can I fix CVE-2020-7451?

To fix CVE-2020-7451, users should update to FreeBSD 12.1-STABLE r358739, 12.1-RELEASE-p3, 11.3-STABLE r358740, or 11.3-RELEASE-p7.

Where can I find more information about CVE-2020-7451?

More information about CVE-2020-7451 can be found at https://security.FreeBSD.org/advisories/FreeBSD-SA-20:04.tcp.asc.