📖 ~4 min read • Source: Amazon Linux advisory ALAS2023-2026-1503
Related CVEs: CVE-2026-3083 CVE-2026-3085 CVE-2026-1940 CVE-2025-47183 CVE-2025-47219
Upstream summary: Heap-based buffer overflow and out-of-bounds write in the RTP QDM2 depayloader. (CVE-2026-3083) Heap-based buffer overflow and out-of-bounds write in the RTP QDM2 depayloader. (CVE-2026-3085)
Table of contents
Symptom & Impact
On Amazon Linux 2023 hosts that have gstreamer1-plugins-good installed, operators report behaviour consistent with Amazon Linux advisory ALAS2023-2026-1503: dnf refuses to install or restart affected services, SELinux AVC denials appear in /var/log/audit/audit.log, and — for security-rated advisories — the host is exposed to the vulnerability set above. Impact ranges from a single service-restart loop on a single EC2 instance to wider availability incidents whenever gstreamer1-plugins-good sits on the serving path of an Auto Scaling group or ECS task.
Environment & Reproduction
Reproduction targets Amazon Linux 2023. Confirm release and the installed package:
cat /etc/system-release
cat /etc/os-release
rpm -q gstreamer1-plugins-good
dnf info gstreamer1-plugins-good | head -20
Trigger the workflow that exposes gstreamer1-plugins-good — multiple vulnerabilities (5 CVEs) — patch and remediation guide while collecting:
sudo journalctl -u gstreamer1-plugins-good -b --no-pager | tail -200
sudo journalctl -xe --no-pager | tail -200
sudo tail -200 /var/log/dnf.log
sudo tail -200 /var/log/audit/audit.log
# For an evidence bundle bundle with sosreport (Amazon Linux ships it):
sudo sosreport --batch
For fleet-wide visibility, query Amazon Inspector and SSM at the same time:
aws inspector2 list-findings
--filter-criteria 'awsAccountId={comparison=EQUALS,value=<account-id>}'
--max-results 50
aws ssm describe-instance-patches --instance-id <i-xxxx> | head -40
Root Cause Analysis
Root cause is documented in Amazon Linux advisory ALAS2023-2026-1503. The Amazon Linux Security Team shipped fixes in the corresponding gstreamer1-plugins-good update for Amazon Linux 2023; running an outdated AMI or unpatched instance leaves the host exposed to the failure modes described in the advisory. Correlate dnf history with system logs:
sudo dnf history | head
sudo dnf history list gstreamer1-plugins-good
sudo dnf history info <id>
sudo ausearch -m AVC,USER_AVC -ts today | tail -100
cat /proc/sys/kernel/tainted # non-zero = tainted kernel / out-of-tree modules
Quick Triage
Run these on Amazon Linux 2023 to capture the current state of gstreamer1-plugins-good:
rpm -q gstreamer1-plugins-good # installed NVR
rpm -V gstreamer1-plugins-good # verify shipped files
sudo dnf check-update --security
sudo dnf updateinfo list cves
systemctl --failed --no-pager
sudo firewall-cmd --list-all 2>/dev/null || sudo iptables -L -n
getenforce && sestatus
# If gstreamer1-plugins-good ships a systemd unit (unit name may differ from pkg name, e.g.
# bind→named, postgresql-server→postgresql, php-fpm→php-fpm):
systemctl list-unit-files | grep -i gstreamer1 | head
Step-by-Step Diagnosis
-
List failed systemd units.
systemctl --failed --no-pager -
Tail the journal for
gstreamer1-plugins-goodand the system bus.sudo journalctl -u gstreamer1-plugins-good -f --no-pager sudo journalctl -xe -f --no-pager -
Inspect firewall / security-group posture from inside the instance.
sudo firewall-cmd --list-all-zones --permanent 2>/dev/null || true sudo nft list ruleset 2>/dev/null | head -50 ss -tulpen | head -
Surface SELinux denials and author a local policy module if needed.
sudo ausearch -m AVC,USER_AVC -ts today sudo ausearch -m AVC -ts today | audit2allow -a -M /tmp/local-fix sudo semodule -i /tmp/local-fix.pp -
Verify
gstreamer1-plugins-goodintegrity and reinstall if anything is altered.sudo rpm -V gstreamer1-plugins-good sudo dnf reinstall -y gstreamer1-plugins-good -
Correlate findings with
/var/log/dnf.log,dnf history, Amazon Inspector findings, and Amazon Linux advisory ALAS2023-2026-1503 to pin the change that introduced gstreamer1-plugins-good — multiple vulnerabilities (5 CVEs) — patch and remediation guide.
Solution – Primary Fix
Apply the corrective dnf transaction referenced by Amazon Linux advisory ALAS2023-2026-1503, then reload affected systemd units:
sudo dnf -y makecache
sudo dnf -y update --security # apply ALL security errata (recommended)
# Or target a single package:
sudo dnf -y update gstreamer1-plugins-good
sudo systemctl daemon-reload
# Unit name may differ from pkg name; check first:
systemctl list-unit-files | grep -i gstreamer1 | head
sudo systemctl restart gstreamer1-plugins-good
rpm -q gstreamer1-plugins-good # confirm new NVR
systemctl is-active gstreamer1-plugins-good 2>/dev/null # confirm running (if a unit exists)
For kernel / glibc / systemd / openssl advisories a reboot is required (or Live Patching where available):
sudo needs-restarting -r # report whether reboot needed
sudo systemctl reboot # or: sudo shutdown -r now
# Amazon Linux Live Patching for the kernel (when enabled on the instance):
sudo dnf install -y kernel-livepatch
sudo dnf kernel-livepatch enable # AL2 / AL2023
sudo dnf kernel-livepatch status
Roll the same change across an Auto Scaling group / fleet with AWS Systems Manager Patch Manager:
aws ssm send-command
--document-name AWS-RunPatchBaseline
--targets Key=tag:Patch,Values=yes
--parameters 'Operation=Install,RebootOption=RebootIfNeeded'
--comment 'Apply Amazon Linux security errata'
aws ssm list-command-invocations --details --max-results 5
# Confirm the patch landed across the fleet:
aws ssm describe-instance-patch-states-for-patch-group
--patch-group <patch-group>
For immutable infrastructure, rebuild the golden AMI in EC2 Image Builder so newly launched instances start patched (do not rely on in-place patching alone):
aws imagebuilder start-image-pipeline-execution
--image-pipeline-arn arn:aws:imagebuilder:<region>:<acct>:image-pipeline/<name>
aws imagebuilder list-images --owner Self --max-results 5
# Then update the launch template / ASG to the new AMI:
aws ec2 create-launch-template-version --launch-template-id <lt-id>
--source-version '$Latest' --launch-template-data 'ImageId=<new-ami-id>'
Need help rolling this patch across an Amazon Linux fleet? Our IT Solutions & Services team manages Amazon Linux fleets with AWS Systems Manager Patch Manager + Inspector + Image Builder pipelines. Get in touch for a free consultation.
Solution – Alternative Approaches
If the primary patch is not viable, choose from these:
-
Roll back the offending dnf transaction:
sudo dnf history list | head sudo dnf history info <id> sudo dnf history undo <id> -
Version-lock the package so dnf cannot upgrade it:
sudo dnf install -y python3-dnf-plugin-versionlock sudo dnf versionlock add gstreamer1-plugins-good sudo dnf versionlock list sudo dnf versionlock delete gstreamer1-plugins-good # remove the lock -
Install an older NVR if a regression is suspected:
dnf --showduplicates list gstreamer1-plugins-good | tac | head sudo dnf install -y --allowerasing gstreamer1-plugins-good-<older-NVR> -
Switch SELinux to permissive briefly to confirm policy is the cause, then re-enforce:
sudo setenforce 0 # reproduce, capture denials, author a custom module: sudo ausearch -m AVC -ts recent | audit2allow -a -M mylocal sudo semodule -i mylocal.pp sudo setenforce 1 -
Take an EBS snapshot of the root volume before kernel / glibc upgrades for fast rollback:
INSTANCE_ID=$(curl -s http://169.254.169.254/latest/meta-data/instance-id) VOL_ID=$(aws ec2 describe-instances --instance-ids $INSTANCE_ID --query 'Reservations[].Instances[].BlockDeviceMappings[?DeviceName==`/dev/xvda`].Ebs.VolumeId' --output text) aws ec2 create-snapshot --volume-id $VOL_ID --description 'pre-patch-snapshot' --tag-specifications 'ResourceType=snapshot,Tags=[{Key=Name,Value=pre-patch}]' -
For immutable workloads, swap the ASG to a previous AMI version instead of patching in place:
aws ec2 describe-launch-template-versions --launch-template-id <lt-id> --max-results 5 aws autoscaling update-auto-scaling-group --auto-scaling-group-name <asg> --launch-template LaunchTemplateId=<lt-id>,Version='<prev-version>' aws autoscaling start-instance-refresh --auto-scaling-group-name <asg> -
Where Kernel Live Patching is enabled, apply kernel fixes without reboot:
sudo dnf kernel-livepatch status sudo dnf kernel-livepatch enable sudo dnf update -y --advisory=ALAS2023-2026-1503 kernel
Verification & Acceptance Criteria
All of these should pass after the fix:
rpm -q gstreamer1-plugins-good # expected fixed NVR
sudo dnf updateinfo list cves --installed # CVEs above no longer listed
systemctl is-active gstreamer1-plugins-good 2>/dev/null
sudo journalctl -u gstreamer1-plugins-good --since "5 minutes ago" --no-pager | grep -iE "error|fail" || echo OK
sudo firewall-cmd --list-services 2>/dev/null || sudo iptables -L -n
getenforce
sudo needs-restarting -r
# Inspector should drop the finding within ~24h:
aws inspector2 list-findings
--filter-criteria 'vulnerabilityId={comparison=EQUALS,value=CVE-2026-3083}'
The original reproduction for gstreamer1-plugins-good — multiple vulnerabilities (5 CVEs) — patch and remediation guide must not trigger across two consecutive runs.
Rollback Plan
Capture state before any change:
rpm -qa > /root/rpm-pre.txt
sudo dnf history list > /root/dnf-history-pre.txt
# Optional pre-patch EBS snapshot of the root volume (run from inside the instance):
INSTANCE_ID=$(curl -s http://169.254.169.254/latest/meta-data/instance-id)
aws ec2 create-snapshot --volume-id <vol-id> --description 'pre-patch'
To revert if the patch is bad:
sudo dnf history undo <id>
# Or downgrade just the package:
sudo dnf install -y --allowerasing gstreamer1-plugins-good-<older-NVR>
sudo systemctl daemon-reload
sudo systemctl restart gstreamer1-plugins-good
# Or replace the instance from a snapshot/older AMI via ASG instance refresh:
aws autoscaling start-instance-refresh --auto-scaling-group-name <asg>
# Custom SELinux policy cleanup:
sudo semodule -r mylocal
Prevention & Hardening
Reduce the chance of this recurring on Amazon Linux 2023:
-
Enable automatic security patching on each instance:
sudo dnf install -y dnf-automatic sudo sed -i 's/^update_cmd.*/update_cmd = security/' /etc/dnf-automatic/dnf-automatic.conf 2>/dev/null || true sudo sed -i 's/^upgrade_type.*/upgrade_type = security/' /etc/dnf/automatic.conf 2>/dev/null || true sudo sed -i 's/^apply_updates.*/apply_updates = yes/' /etc/dnf/automatic.conf 2>/dev/null || true sudo systemctl enable --now dnf-automatic.timer -
Drive fleet-wide patching through AWS Systems Manager Patch Manager (preferred for any fleet bigger than a handful of instances):
aws ssm send-command --document-name AWS-RunPatchBaseline --targets Key=tag:Patch,Values=yes --parameters 'Operation=Install,RebootOption=RebootIfNeeded' aws ssm describe-patch-baselines --filters Key=OWNER,Values=AWS aws ssm get-default-patch-baseline --operating-system AMAZON_LINUX_2023 -
Enable Amazon Inspector for continuous CVE / package vulnerability scanning:
aws inspector2 enable --resource-types EC2 ECR LAMBDA aws inspector2 list-findings --filter-criteria 'severity={comparison=EQUALS,value=HIGH}' --max-results 20 aws inspector2 batch-get-account-status -
Bake patched golden AMIs with EC2 Image Builder and roll them via ASG instance refresh instead of in-place patching for immutable infrastructure:
aws imagebuilder list-image-pipelines aws imagebuilder start-image-pipeline-execution --image-pipeline-arn arn:aws:imagebuilder:<region>:<acct>:image-pipeline/<name> aws autoscaling start-instance-refresh --auto-scaling-group-name <asg> -
Subscribe to alas.aws.amazon.com and watch AWS security bulletins for upstream changes.
-
Version-lock sensitive packages so they cannot be auto-upgraded:
sudo dnf install -y python3-dnf-plugin-versionlock sudo dnf versionlock add gstreamer1-plugins-good -
Monitor file integrity with AIDE:
sudo dnf install -y aide sudo aide --init && sudo mv /var/lib/aide/aide.db.new.gz /var/lib/aide/aide.db.gz sudo aide --check -
Enable Kernel Live Patching so kernel CVEs can be remediated without reboot:
sudo dnf install -y kernel-livepatch sudo dnf kernel-livepatch enable sudo dnf kernel-livepatch status -
Keep SELinux in enforcing mode and review custom modules in
/etc/selinux/targeted/after every package upgrade. -
Apply CIS Amazon Linux 2023 Benchmark hardening and remove unused packages.
Related Errors & Cross-Refs
Issues that commonly surface alongside gstreamer1-plugins-good — multiple vulnerabilities (5 CVEs) — patch and remediation guide: dnf lock contention, systemd unit ordering cycles, SELinux AVC bursts, security-group / NACL drift, and kernel taint flags after out-of-tree modules. Useful triage:
sudo dnf check
systemd-analyze critical-chain
sudo ausearch -m AVC -ts today | tail
sudo firewall-cmd --get-active-zones 2>/dev/null || sudo iptables -L -n
cat /proc/sys/kernel/tainted
sudo needs-restarting -r
aws ssm describe-instance-patches --instance-id <i-xxxx> | tail -40
View all amazon-linux-2023 tutorials on the Tutorials Hub →
Browse all common problems & solutions on the Tutorials Hub.
References & Further Reading
Primary reference: Amazon Linux advisory ALAS2023-2026-1503. Manual pages useful on Amazon Linux 2023:
man dnf
man dnf.conf
man systemctl
man journalctl
man firewall-cmd
man semanage
man audit2allow
man sosreport
Other resources: alas.aws.amazon.com, SSM Patch Manager docs, Amazon Inspector docs, EC2 Image Builder docs, and per-package notes in /usr/share/doc/gstreamer1-plugins-good/ for components implicated in gstreamer1-plugins-good — multiple vulnerabilities (5 CVEs) — patch and remediation guide.