Overview
For our 200th episode, we discuss the impact of Red Hat’s decision to stop
publicly releasing the RHEL source code, plus we cover security updates for
libX11, GNU SASL, QEMU, VLC, pngcheck, the Linux kernel and a whole lot more.
This week in Ubuntu Security Updates
[USN-6163-1] pano13 vulnerabilities (01:08)
2 CVEs addressed in Trusty ESM (14.04 ESM), Xenial ESM (16.04 ESM), Bionic ESM (18.04 ESM), Focal (20.04 LTS), Jammy (22.04 LTS)CVE-2021-33293 CVE-2021-20307 use by hugin-tools for stitching together photos into a panoramaformat-string vuln in PTcrop utility which could be abused to execute arbitrary code etcOOB read (looks more like a NULL ptr deref from the upstream patch…) whenparsing TIFF images
[USN-6168-1, USN-6168-2] libx11 vulnerability (01:55)
1 CVEs addressed in Trusty ESM (14.04 ESM), Xenial ESM (16.04 ESM), Bionic ESM (18.04 ESM), Focal (20.04 LTS), Jammy (22.04 LTS), Kinetic (22.10), Lunar (23.04)CVE-2023-3138 libx11 mishandled various Request, Event and Error IDs - these IDs get used asindexes into various arrays and so can be used to trigger OOB writes up -
these IDs get supplied back from the X server to the X client - if were
tricked into connecting to a malicious X server, could then either crash X
client -> DoS or get code execution - in general, it is highly unlikely to be
tricked into connecting to a malicious X server due to the nature of the X
protocol (as the X server usually runs on the local machine)
[USN-6169-1] GNU SASL vulnerability (03:22)
1 CVEs addressed in Trusty ESM (14.04 ESM), Xenial ESM (16.04 ESM), Bionic ESM (18.04 ESM), Focal (20.04 LTS), Jammy (22.04 LTS)CVE-2022-2469 library and CLI application for the Simple Authentication and Security Layer(SASL) framework - used by network servers like IMAP/XMPP etc and to
authenticate clients etc
e.g. mutt and neomutt both use thisPossible OOB read on server side if client provides crafted auth data -> DoS /info leak against the server
[USN-6155-2] Requests vulnerability (04:02)
1 CVEs addressed in Xenial ESM (16.04 ESM), Bionic ESM (18.04 ESM)CVE-2023-32681 [USN-6155-1] Requests vulnerability from Episode 199[USN-6166-2] libcap2 vulnerability (04:21)
1 CVEs addressed in Trusty ESM (14.04 ESM), Xenial ESM (16.04 ESM), Bionic ESM (18.04 ESM)CVE-2023-2603 [USN-6166-1] libcap2 vulnerabilities from Episode 199[USN-6083-2] cups-filters vulnerability (04:30)
1 CVEs addressed in Xenial ESM (16.04 ESM)CVE-2023-24805 [USN-6083-1] cups-filters vulnerability from Episode 196[USN-6156-2] SSSD regression (04:40)
Affecting Focal (20.04 LTS)[USN-6156-1] SSSD vulnerability from Episode 199possible issue if were to install only some of the newer binary packages fromthe previous security update - fixed by adding more specific dependency info
in the package metadata but ideally users should just run apt upgrade or use
unattended-upgrades to install security updates as this will upgrade all
installed binary packages to all the newer versions, and not say just apt install sssd which would only pull in some of the binary packages
[USN-6167-1] QEMU vulnerabilities (05:31)
4 CVEs addressed in Trusty ESM (14.04 ESM), Xenial ESM (16.04 ESM), Bionic ESM (18.04 ESM), Focal (20.04 LTS), Jammy (22.04 LTS), Kinetic (22.10), Lunar (23.04)CVE-2023-0330 CVE-2022-4172 CVE-2022-4144 CVE-2022-1050 All various memory management issues in different guest drivers, which couldallow a malicious guest to cause QEMU on the host to crash - not really
surprising as the boundary between unprivileged and privileged components is
the literal attack surface in this case and so is where security issues of
this nature will likely be found
[USN-6176-1] PyPDF2 vulnerability (05:57)
1 CVEs addressed in Xenial ESM (16.04 ESM), Bionic ESM (18.04 ESM), Focal (20.04 LTS), Jammy (22.04 LTS)CVE-2022-24859 Library for handling PDF filesPossible infinite loop if input PDF was malformed and finished withoutcontaining an expected terminating element - would just keep trying to read
even though there was nothing more to read
[USN-6170-1] Podman vulnerabilities (06:26)
Affecting Jammy (22.04 LTS)When using podman play kube to create containers / pods / volumes based on ak8s yaml, it would always pull in the k8s.gcr.io/pause image - this is not
necessary and it not necessarily maintained and so could present a security
issue as a result
[USN-6177-1, USN-6179-1] Jettison vulnerabilities (07:01)
4 CVEs addressed in Xenial ESM (16.04 ESM), Bionic ESM (18.04 ESM), Focal (20.04 LTS), Jammy (22.04 LTS), Kinetic (22.10)CVE-2022-45693 CVE-2022-45685 CVE-2022-40150 CVE-2022-40149 1 CVEs addressed in Xenial ESM (16.04 ESM), Bionic ESM (18.04 ESM), Focal (20.04 LTS), Jammy (22.04 LTS), Kinetic (22.10), Lunar (23.04)CVE-2023-1436 Java library for converting between XML and JSON3 different stack overflows due to recursive parsing implementation for JSON -so could simply create a JSON structure that had a very deeply nested object
to trigger this - plus an associated memory leak -> OOM - fixed by counting
number of recursions and bailing if get too deep
[USN-6178-1] SVG++ library vulnerabilities (07:37)
2 CVEs addressed in Bionic ESM (18.04 ESM), Jammy (22.04 LTS), Kinetic (22.10)CVE-2021-44960 CVE-2019-6246 Possible OOB reads - one in demo code only - not much of a security impact -still assigned CVSS 6.5 for NULL ptr deref in demo code - shows the limits of
CVSS as a metric - Daniel Stenberg (curl maintainer) has a good discussion of
this on his blog -
https://daniel.haxx.se/blog/2023/03/06/nvd-makes-up-vulnerability-severity-levels/https://daniel.haxx.se/blog/2023/06/12/nvd-damage-continued/I even wrote something about this a few years ago -https://ubuntu.com/blog/securing-open-source-through-cve-prioritisation -
there is more to CVEs than just their CVSS score - also CVSS 4 will help a bit
but will still not capture enough nuance, and even if it does, it still won’t
stop the problem of CVEs being misclassified due to a lack of deep
understanding by whoever assigns the CVSS score (and in fact this may be made
worse by CVSS 4 since it contains more attributes used to compute a score)
[USN-6180-1] VLC media player vulnerabilities (09:58)
7 CVEs addressed in Xenial ESM (16.04 ESM), Bionic ESM (18.04 ESM), Focal (20.04 LTS), Jammy (22.04 LTS), Kinetic (22.10)CVE-2022-41325 CVE-2021-25804 CVE-2021-25803 CVE-2021-25802 CVE-2021-25801 CVE-2020-13428 CVE-2019-19721 OOB reads / write when handling various image or video files -> DoS / RCE[USN-5948-2] Werkzeug vulnerabilities (10:16)
2 CVEs addressed in Lunar (23.04)CVE-2023-25577 CVE-2023-23934 various utilities for WSGI applications in pythonone issue in cookie parsing which could allow a remote attacker to shadowother cookies, another CPU-based DoS via unlimited number of multipart form
data parts - since each consumes only a small number of bytes but takes a
reasonable amount of CPU time to parse (and also consumes RAM too)
[USN-6143-3] Firefox regressions (11:09)
4 CVEs addressed in Focal (20.04 LTS)CVE-2023-34415 CVE-2023-34417 CVE-2023-34416 CVE-2023-34414 114.0.2 - Upstream regressions in native messaging handlers and some possible crashes as well[USN-6181-1] Ruby vulnerabilities (11:24)
3 CVEs addressed in Kinetic (22.10), Lunar (23.04)CVE-2023-28756 CVE-2023-28755 CVE-2021-33621 2 different ReDoS, 1 issue in handling of responses in the cgi gem could allowan attacker to modify the response that would then be received by the user via
a HTTP response splitting attack
[USN-6182-1] pngcheck vulnerabilities (11:51)
2 CVEs addressed in Xenial ESM (16.04 ESM), Bionic ESM (18.04 ESM), Focal (20.04 LTS)CVE-2020-35511 CVE-2020-27818 Used to verify the integrity of PNG and associated files (used by theforensics-extra package which contains various forensics and ethical hacking
tools etc)
Ironically this contained a buffer overflow which could be triggered on acrafted file
[USN-6171-1] Linux kernel vulnerabilities (12:29)
9 CVEs addressed in Jammy (22.04 LTS), Kinetic (22.10)CVE-2023-2985 CVE-2023-25012 CVE-2023-1998 CVE-2023-1859 CVE-2023-1670 CVE-2023-1079 CVE-2023-1077 CVE-2023-1076 CVE-2022-4269 5.1922.10 - generic, AWS, Azure. GCP, KVM, Oracle, Raspi, Lowlatency22.04 - HWEVarious issues allowing local user to trigger deadlock, OOPS (crash), or readkernel memory (info leak) - none appear to be exploitable remotely
[USN-6172-1] Linux kernel vulnerabilities (13:02)
8 CVEs addressed in Focal (20.04 LTS), Jammy (22.04 LTS)CVE-2023-2985 CVE-2023-25012 CVE-2023-1998 CVE-2023-1859 CVE-2023-1670 CVE-2023-1079 CVE-2023-1077 CVE-2023-1076 5.1522.04 generic, GCP, GKE, Raspi, AWS, Azure, Oracle, KVM, lowlatency etc5.420.04 generic, GCP, GKE, Raspi, AWS, Azure, Oracle, KVM, lowlatency etcSimilar set of issues as above[USN-6173-1] Linux kernel (OEM) vulnerabilities (13:32)
7 CVEs addressed in Jammy (22.04 LTS)
CVE-2023-32254 CVE-2023-32250 CVE-2023-2269 CVE-2023-2156 CVE-2023-2002 CVE-2023-1380 CVE-2023-31436 OOB read in the USB handling code for Broadcom FullMAC USB WiFi driver
requires an attacker to create a malicious USB device and insert that intoyour machine to be able to trigger (shout out to USBGuard)
OOB write in network queuing scheduler
able to be triggered though an unprivileged user namespace (again)[USN-6130-1] Linux kernel vulnerabilities from Episode 198
[USN-6174-1] Linux kernel (OEM) vulnerabilities
3 CVEs addressed in Jammy (22.04 LTS)CVE-2023-26606 CVE-2023-1073 CVE-2023-0459 5.17 OEM[USN-6175-1] Linux kernel vulnerabilities (14:11)
20 CVEs addressed in Lunar (23.04)CVE-2023-33288 CVE-2023-33203 CVE-2023-30772 CVE-2023-28866 CVE-2023-28466 CVE-2023-2612 CVE-2023-2235 CVE-2023-2194 CVE-2023-1990 CVE-2023-1989 CVE-2023-1859 CVE-2023-1855 CVE-2023-1670 CVE-2023-1611 CVE-2023-1583 CVE-2022-4269 CVE-2023-1380 CVE-2023-30456 CVE-2023-31436 CVE-2023-32233 6.2 GA (everything)[USN-6130-1] Linux kernel vulnerabilities from Episode 198[LSN-0095-1] Linux kernel vulnerability (14:25)
6 CVEs addressed in Bionic ESM (18.04 ESM), Focal (20.04 LTS), Jammy (22.04 LTS)CVE-2023-32233 CVE-2023-31436 CVE-2023-2612 CVE-2023-1872 CVE-2023-1380 CVE-2023-0386
Kernel type
22.04
20.04
18.04
aws
95.4
95.4
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aws-5.15
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95.4
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aws-5.4
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95.4
azure
95.4
95.4
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azure-5.4
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95.4
gcp
95.4
95.4
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gcp-5.15
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95.4
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gcp-5.4
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95.4
generic-5.4
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95.4
95.4
gke
95.4
95.4
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gke-5.15
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95.4
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gke-5.4
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95.4
gkeop
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95.4
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gkeop-5.4
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95.4
ibm
95.4
95.4
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ibm-5.4
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95.4
linux
95.4
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lowlatency
95.1
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lowlatency-5.4
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95.4
95.4
To check your kernel type and Livepatch version, enter this command:
canonical-livepatch status
Goings on in Linux Security Community
Red Hat to stop publicly releasing source code for RHEL (14:59)
https://www.redhat.com/en/blog/furthering-evolution-centos-streamPreviously would release sources for RHEL to git.centos.org - the repo whichwas used for the previous CentOS Linux - a freely available repackaging of
RHEL, more like a downstream - was discontinued at the end of 2021 in favour
of CentOS Stream which is positioned more as an upstream of RHEL now.
By pushing these sources public, allowed others to inspect their work, butalso to create competitor products based off that work - AlmaLinux / Rocky
etc - both of which aim to be community versions of RHEL, bug-for-bug
compatible etc
https://almalinux.org/blog/impact-of-rhel-changes/https://rockylinux.org/news/2023-06-22-press-release/This change first occurred last week, noticed by the AlmaLinux developers -RHEL then released the public statement above
Red Hat say CentOS Stream will now be the only public repo for RHEL-relatedsource code - but this does not necessarily contain all the patches and
updates that end up in the various RHEL packages
AlmaLinux plans to then use CentOS Stream to base their security updatesoff - as this is still public
Rocky Linux is not so open about how they plan to deal with this - alsolooks like they will use CentOS Stream as their upstream - but will this
then be bug-for-bug compatible with RHEL as they claim?
Red Hat also say the sources for RHEL will be available to customers andpartners via their usual customer portal - however the standard RHEL license
agreement prohibits these from being used to develop competitor products etc
Doesn’t have a huge impact on Ubuntu as in general we take our patches directfrom the upstream projects - and when we have to backport these to older
versions, they are not necessarily the same version as used in RHEL anyway so
we don’t often use patches from RHEL
Will be interesting to see what impact this does have on AlmaLinux and RockyLinux
Get in contact
[email protected]#ubuntu-security on the Libera.Chat IRC networkubuntu-hardened mailing listSecurity section on discourse.ubuntu.com@[email protected], @ubuntu_sec on twitter