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Debian Security Advisory DSA-5095-1                   security@debian.org
https://www.debian.org/security/                     Salvatore Bonaccorso
March 09, 2022                        https://www.debian.org/security/faq
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Package        : linux
CVE ID         : CVE-2020-36310 CVE-2022-0001 CVE-2022-0002 CVE-2022-0487
                 CVE-2022-0492 CVE-2022-0617 CVE-2022-25636
Debian Bug     : 990279

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

CVE-2020-36310

    A flaw was discovered in the KVM implementation for AMD processors,
    which could lead to an infinite loop.  A malicious VM guest could
    exploit this to cause a denial of service.

CVE-2022-0001 (INTEL-SA-00598)

    Researchers at VUSec discovered that the Branch History Buffer in
    Intel processors can be exploited to create information side-
    channels with speculative execution.  This issue is similar to
    Spectre variant 2, but requires additional mitigations on some
    processors.

    This can be exploited to obtain sensitive information from a
    different security context, such as from user-space to the kernel,
    or from a KVM guest to the kernel.

CVE-2022-0002 (INTEL-SA-00598)

    This is a similar issue to CVE-2022-0001, but covers exploitation
    within a security context, such as from JIT-compiled code in a
    sandbox to hosting code in the same process.

    This is partly mitigated by disabling eBPF for unprivileged users    with the sysctl: kernel.unprivileged_bpf_disabled=2.  This is
    already the default in Debian 11 "bullseye".

CVE-2022-0487

    A use-after-free was discovered in the MOXART SD/MMC Host Controller
    support driver. This flaw does not impact the Debian binary packages
    as CONFIG_MMC_MOXART is not set.

CVE-2022-0492

    Yiqi Sun and Kevin Wang reported that the cgroup-v1 subsystem does
    not properly restrict access to the release-agent feature. A local
    user can take advantage of this flaw for privilege escalation and
    bypass of namespace isolation.

CVE-2022-0617

    butt3rflyh4ck discovered a NULL pointer dereference in the UDF
    filesystem. A local user that can mount a specially crafted UDF
    image can use this flaw to crash the system.

CVE-2022-25636

    Nick Gregory reported a heap out-of-bounds write flaw in the
    netfilter subsystem. A user with the CAP_NET_ADMIN capability could
    use this for denial of service or possibly for privilege escalation.

For the stable distribution (bullseye), these problems have been fixed
in version 5.10.103-1.  This update additionally includes many more
bug fixes from stable updates 5.10.93-5.10.103 inclusive.

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

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