Security Information / 2023 / Security Information -- DSA-5462-1 linux

Debian Security Advisory

DSA-5462-1 linux -- security update

Date Reported:

30 Jul 2023

Affected Packages:

linux

Vulnerable:

Yes

Security database references:

In Mitre's CVE dictionary: CVE-2023-20593.

More information:

Tavis Ormandy discovered that under specific microarchitectural circumstances, a vector register in AMD Zen 2 CPUs may not be written to 0 correctly. This flaw allows an attacker to leak sensitive information across concurrent processes, hyper threads and virtualized guests.

For details please refer to https://lock.cmpxchg8b.com/zenbleed.html and https://github.com/google/security-research/security/advisories/GHSA-v6wh-rxpg-cmm8

This issue can also be mitigated by a microcode update through the amd64-microcode package or a system firmware (BIOS/UEFI) update. However, the initial microcode release by AMD only provides updates for second generation EPYC CPUs. Various Ryzen CPUs are also affected, but no updates are available yet.

For the stable distribution (bookworm), this problem has been fixed in version 6.1.38-2.

We recommend that you upgrade your linux packages.

For the detailed security status of linux please refer to its security tracker page at: https://security-tracker.debian.org/tracker/linux