Multiple lwIP Vulnerabilities Affecting Ubuntu 20.04 LTS

On June 11, 2026, Ubuntu released USN-8423-1 addressing several vulnerabilities in the lwIP TCP/IP stack. The vulnerabilities include a buffer overflow in EAP authentication (CVE-2020-8597), improper handling of ICMPv6 packets (CVE-2020-22283, CVE-2020-22284), and a stack-based buffer overflow due to SNMPv3 parameter validation issues (CVE-2026-8836). All reported issues primarily affect Ubuntu 20.04 LTS, with potential for arbitrary code execution or denial of service. The vulnerabilities were confirmed and patched, and users are advised to update their systems to mitigate risks. The advisory highlights the importance of regular updates to maintain security. The vulnerabilities were first disclosed between 2020 and 2026, with the latest CVE published on May 18, 2026.

Key Points: • Multiple vulnerabilities in lwIP affect Ubuntu 20.04 LTS, with potential for serious exploitation. • CVE-2020-8597 allows for arbitrary code execution or denial of service via buffer overflow. • Users are urged to update their systems to the latest package versions to mitigate risks.