QUIC ACK-only Packet Retention Can Cause Memory Exhaustion
Description
To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle
Affected software
pkg:deb/ubuntu/nodejs?arch=source&distro=esm-apps/xenialpkg:deb/ubuntu/nodejs?arch=source&distro=esm-apps/bionicpkg:deb/ubuntu/openssl-fips?arch=source&distro=fips-preview/jammypkg:deb/ubuntu/openssl-fips?arch=source&distro=fips-updates/jammypkg:deb/ubuntu/openssl-fips?arch=source&distro=fips-updates/noblepkg:deb/ubuntu/edk2?arch=source&distro=resolutepkg:deb/ubuntu/openssl?arch=source&distro=resoluteRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-63075 is a vulnerability in OpenSSL where improper handling of QUIC ACK-only packet retention can cause the software to consume excessive resources, potentially resulting in a denial of service condition. This issue specifically affects Ubuntu 26.04 LTS and certain OpenSSL package versions. The vulnerability is due to incorrect resource management in the QUIC server incoming channel queue. The vendor advisory from Ubuntu (USN-8678-1) confirms the issue and provides patched package versions to address it.
Potential Impact
A remote attacker could exploit this vulnerability to cause OpenSSL to consume excessive system resources, leading to denial of service on affected systems. There is no indication of code execution or data compromise. The impact is limited to resource exhaustion and service disruption.
Mitigation Recommendations
A patch is available and should be applied by updating the OpenSSL packages to the fixed versions listed in the Ubuntu security notice USN-8678-1. After applying the update, a system reboot is recommended to ensure all changes take effect. No additional mitigation actions are specified or required by the vendor.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- UBUNTU-CVE-2026-63075
- Osv Schema Version
- 1.7.0
- Ecosystems
- ["Ubuntu:Pro:16.04:LTS","Ubuntu:Pro:18.04:LTS","Ubuntu:Pro:FIPS-preview:22.04:LTS","Ubuntu:Pro:FIPS-updates:22.04:LTS","Ubuntu:Pro:FIPS-updates:24.04:LTS","Ubuntu:26.04:LTS"]
- Cvss Version
- 3.1
Patch Information
Threat ID: 6a9053e7acd9273b49696875
Added to database: 08/27/2026, 15:12:39 UTC
Last enriched: 09/10/2026, 07:55:26 UTC
Last updated: 10/10/2026, 18:48:21 UTC
Views: 70
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