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Debian Security Advisory DSA-5461-1                   security@debian.org
https://www.debian.org/security/                     Salvatore Bonaccorso
July 30, 2023                         https://www.debian.org/security/faq
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Package        : linux
CVE ID         : CVE-2023-3390 CVE-2023-3610 CVE-2023-20593

Several vulnerabilities have been discovered in the Linux kernel that
may lead to a privilege escalation, denial of service or information
leaks.

CVE-2023-3390

    A use-after-free flaw in the netfilter subsystem caused by incorrect
    error path handling may result in denial of service or privilege
    escalation.

CVE-2023-3610

    A use-after-free flaw in the netfilter subsystem caused by incorrect
    refcount handling on the table and chain destroy path may result in
    denial of service or privilege escalation.

CVE-2023-20593

    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
     and
    .

    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 oldstable distribution (bullseye), these problems have been fixed
in version 5.10.179-3.

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/source-package/linux

Further information about Debian Security Advisories, how to apply
these updates to your system and frequently asked questions can be
found at: https://www.debian.org/security/

Mailing list: debian-security-announce@lists.debian.org