# CVE-2026-50107 — F5 NGINX Gateway Fabric

> As of 2026-06-18, CVE-2026-50107 is a HIGH-severity vulnerability in F5 NGINX Gateway Fabric, CVSS v3.1 8.1, EPSS 0.4% (38.5th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-50107, most recently “F5 Out-of-Band Patches for Critical NGINX HTTP/3 Use-After-Free and Proxy/gRPC Heap Overflow (CVE-2026-42530, CVE-2026-42055) plus NGINX Gateway Fabric Config Injection (CVE-2026-11311, CVE-2026-50107)”.

**Last updated:** 2026-06-18

## What is CVE-2026-50107?

When NGINX Plus or NGINX Open Source is configured as the data plane for NGINX Gateway Fabric, an injection vulnerability exists in the NGINX configuration generator component of NGINX Gateway Fabric. User-supplied string values from the NginxProxy Custom Resource Definition (CRD) access log format setting are rendered directly into NGINX configuration templates without sanitization or escaping. An authenticated attacker with permission to create or modify these CRDs may craft values that inject arbitrary NGINX configuration directives. This is a control plane issue; there is no data plane exposure from the vulnerability trigger itself. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

The record classifies CVE-2026-50107 under weakness class [CWE-74](https://cwe.mitre.org/data/definitions/74.html). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs low-privilege credentials, needs no user interaction, and has high impact on confidentiality, integrity. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 87 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 8.1 — HIGH (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N`)
- **CVSS v4.0 base score:** 8.6 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N`)
- **EPSS (FIRST):** 0.4% probability of exploitation in the next 30 days, higher than 38.5% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 5.6/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-06-17, last modified 2026-06-18

## Is CVE-2026-50107 being exploited?

No public exploitation evidence for CVE-2026-50107 is recorded in the sources Threadlinqs tracks — CISA KEV, Exploit-DB, public proof-of-concept repositories and ProjectDiscovery Nuclei — as of 2026-06-18. That is an absence of evidence in those feeds, not a guarantee that the vulnerability is unexploited.

## Affected products and versions

- **F5**: NGINX Gateway Fabric

## How to fix CVE-2026-50107

Vendor advisory: [https://my.f5.com/manage/s/article/K000161785](https://my.f5.com/manage/s/article/K000161785). Apply the vendor fix referenced above to every affected product listed in this record, then confirm the running version against the vendor advisory.

## Threat activity tracking CVE-2026-50107

1 tracked threat in the Threadlinqs corpus references CVE-2026-50107, either in the campaign’s CVE list or as an indicator on the campaign record.

- [F5 Out-of-Band Patches for Critical NGINX HTTP/3 Use-After-Free and Proxy/gRPC Heap Overflow (CVE-2026-42530, CVE-2026-42055) plus NGINX Gateway Fabric Config Injection (CVE-2026-11311, CVE-2026-50107)](https://intel.threadlinqs.com/threat/TL-2026-0848) — CRITICAL · 2026-06-18

## Sources

Enriched from CVE.org, NVD, FIRST EPSS, GitHub Security Advisories. Last verified by Threadlinqs on 2026-06-25. This product uses the NVD API but is not endorsed or certified by the NVD.

**Vendor advisory and patch**

- [my.f5.com — vendor advisory](https://my.f5.com/manage/s/article/K000161785)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-50107
Full detection coverage and IOCs for threats exploiting CVE-2026-50107 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp