USN-4746-1: xterm vulnerability

Tavis Ormandy discovered that xterm incorrectly handled certain character
sequences. A remote attacker could use this issue to cause xterm to crash,
resulting in a denial of service, or possibly execute arbitrary code.

USN-4698-2: Dnsmasq regression

USN-4698-1 fixed vulnerabilities in Dnsmasq. The updates introduced
regressions in certain environments related to issues with multiple
queries, and issues with retries. This update fixes the problem.

Original advisory details:

Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly handled
memory when sorting RRsets. A remote attacker could use this issue to cause
Dnsmasq to hang, resulting in a denial of service, or possibly execute
arbitrary code. (CVE-2020-25681, CVE-2020-25687)

Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly handled
extracting certain names. A remote attacker could use this issue to cause
Dnsmasq to hang, resulting in a denial of service, or possibly execute
arbitrary code. (CVE-2020-25682, CVE-2020-25683)

Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly
implemented address/port checks. A remote attacker could use this issue to
perform a cache poisoning attack. (CVE-2020-25684)

Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly
implemented query resource name checks. A remote attacker could use this
issue to perform a cache poisoning attack. (CVE-2020-25685)

Moshe Kol and Shlomi Oberman discovered that Dnsmasq incorrectly handled
multiple query requests for the same resource name. A remote attacker could
use this issue to perform a cache poisoning attack. (CVE-2020-25686)

It was discovered that Dnsmasq incorrectly handled memory during DHCP
response creation. A remote attacker could possibly use this issue to
cause Dnsmasq to consume resources, leading to a denial of service. This
issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04
LTS. (CVE-2019-14834)

USN-4745-1: OpenSSL vulnerabilities

David Benjamin discovered that OpenSSL incorrectly handled comparing
certificates containing a EDIPartyName name type. A remote attacker could
possibly use this issue to cause OpenSSL to crash, resulting in a denial of
service. (CVE-2020-1971)

Tavis Ormandy discovered that OpenSSL incorrectly handled parsing issuer
fields. A remote attacker could possibly use this issue to cause OpenSSL to
crash, resulting in a denial of service. (CVE-2021-23841)

How To: Enable a Swapfile

no swapfile

[code]sudo fallocate -l 8G /swapfile[/code]

Why 8 gigabytes when I have ample RAM and an SSD? Because I never, ever want to worry about it again. I want to be able to open up every app I have and leave them open for a month. You do you and decide how big you want it to be!

[code]sudo chmod 600 /swapfile[/code]

[code]sudo mkswap /swapfile[/code]

And turn it on with:

[code]sudo swapon /swapfile[/code]

[code]sudo nano /etc/fstab[/code]

And add this at the bottom of that document:

[code]/swapfile none swap sw 0 0[/code]

USN-4467-3: QEMU regression

USN-4467-1 fixed vulnerabilities in QEMU. The fix for CVE-2020-13754
introduced a regression in certain environments. This update fixes the
problem.

We apologize for the inconvenience.

Original advisory details:

Ren Ding, Hanqing Zhao, Alexander Bulekov, and Anatoly Trosinenko
discovered that the QEMU incorrectly handled certain msi-x mmio operations.
An attacker inside a guest could possibly use this issue to cause QEMU to
crash, resulting in a denial of service. (CVE-2020-13754)