--- title: "CVE-2026-103994: Juniper Networks Junos OS - Heap-based Buffer Overflow" description: "Juniper Networks Junos OS contains a heap-based buffer overflow caused by improper handling in VXLAN Gateway Daemon (vgd), letting malicious or compromised SDN-controller cause outage or remote code execution, exploit requires malicious SDN-controller." url: https://panop.io/threat-heartbeat/CVE-2026-103994/ --- # CVE-2026-103994 Juniper Networks Junos OS - Heap-based Buffer Overflow Juniper Networks Junos OS contains a heap-based buffer overflow caused by improper handling in VXLAN Gateway Daemon (vgd), letting malicious or compromised SDN-controller cause outage or remote code execution, exploit requires malicious SDN-controller. CVSS base score 8.8 /10 High CISA KEV Not listed Public exploit None known Authentication Not required [View the NVD record ↗](https://nvd.nist.gov/vuln/detail/CVE-2026-103994) ## Details Type Heap-based Buffer Overflow Impact Remote Code Execution, Denial Of Service CVSS vector CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Published 14 October 2026 Updated 15 October 2026 Weakness [CWE-122](https://cwe.mitre.org/data/definitions/122.html) ## Vendor fix Update to the latest Junos OS version containing the fix. Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them. ## References - [https://nvd.nist.gov/vuln/detail/CVE-2026-103994](https://nvd.nist.gov/vuln/detail/CVE-2026-103994) - [https://supportportal.juniper.net/JSA112188](https://supportportal.juniper.net/JSA112188) [← All CVEs](https://panop.io/threat-heartbeat/) ## What this record can't tell you - Whether you run the affected software, and where - Whether an attacker can actually reach and exploit it - The misconfigurations that never get a CVE number - What it would cost the business, ranked into what to fix first Panop answers these inside your environment, for this CVE and every other finding. [Book a demo](https://panop.io/demo)