NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_ssi_module module. This vulnerability may exist when the Server-Side Includes (SSI), proxy_pass, and proxy_buffering off directives are configured. With this configuration, an unauthenticated attacker with man-in-the-middle (MITM) ability to control responses from an upstream server may be able to cause a use-after-free in the NGINX worker process. This issue may lead to limited modification of memory or a restart of the NGINX worker process. Impact: This vulnerability may allow remote attackers to have limited control to modify memory contents or restart the NGINX worker process. There is no control plane exposure; this is a data plane issue only. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
This vulnerability carries a MEDIUM severity rating with a CVSS v3.1 score of 6.5, indicating it can be exploited remotely over the network but requires specific conditions to be met without requiring user interaction and does not require pre-existing privileges . The vulnerability impacts limited integrity, and availability (service disruption) for affected systems. Impacting 4 products from f5, from f5, from f5 and 1 other, organizations running these solutions should prioritize assessment and patching.
Reported in 2026, this vulnerability emerged during an era marked by increased sophistication in supply chain attacks, cloud infrastructure vulnerabilities, and software-as-a-service (SaaS) security challenges. Security practices during this period emphasized zero-trust architectures, container security, and API protection.
2026-07-15T15:16:45.700
2026-08-10T15:27:56.373
Analyzed
CVSSv3.1: 6.5 (MEDIUM)
| Type | Vendor | Product | Version/Range | Vulnerable? |
|---|---|---|---|---|
| Application | f5 | nginx_gateway_fabric | ≤ 1.6.2 | Yes |
| Application | f5 | nginx_gateway_fabric | < 2.6.7 | Yes |
| Application | f5 | nginx_ingress_controller | ≤ 3.7.2 | Yes |
| Application | f5 | nginx_ingress_controller | < 5.5.3 | Yes |
| Application | f5 | nginx_ingress_controller | < 2026-lts-r4 | Yes |
| Application | f5 | nginx_ingress_controller | 4.0.0 | Yes |
| Application | f5 | nginx_ingress_controller | 4.0.1 | Yes |
| Application | f5 | nginx_plus | < 37.0.3.1 | Yes |
| Application | f5 | nginx_plus | < r36 | Yes |
| Application | f5 | nginx_plus | r36 | Yes |
| Application | f5 | nginx_plus | r36 | Yes |
| Application | f5 | nginx_plus | r36 | Yes |
| Application | f5 | nginx_plus | r36 | Yes |
| Application | f5 | nginx_plus | r36 | Yes |
| Application | f5 | nginx_plus | r36 | Yes |
| Application | f5 | nginx_plus | r36 | Yes |
| Application | f5 | waf | ≤ 4.16.0 | Yes |
| Application | f5 | waf | ≤ 5.8.0 | Yes |
| Application | f5 | waf | < 5.13.4 | Yes |
SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For f5's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.