CVE-2026-103994: juniper networks junos os Heap-based Buffer Overflow

Vulnerability summary

CVE-2026-103994 is a high (CVSS 8.8) Heap-based Buffer Overflow vulnerability in juniper networks junos os. EPSS estimates a 0.43% chance of exploitation in the next 30 days, higher than 35.7% of scored vulnerabilities.

Timeline

1. 14-10-2026
   PublishedVulnerability first disclosed.
2. 15-10-2026
   Last modifiedVulnerability information updated.

Description

A Heap-based Buffer Overflow vulnerability in the VXLAN Gateway Daemon (vgd) of Juniper Networks Junos OS allows a malicious or compromised SDN-controller to cause a complete outage of the OVSDB control plane and possibly remote code execution.

• CWE-122Heap-based Buffer OverflowA heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().