Vulnerability · Published Sep 15, 2026 · Assigned by f5
CVE-2026-90439NGINX ngx_http_v3_module vulnerability
Medium 6.5
In plain English
A medium-severity heap buffer overflow in NGINX Open Source from F5. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 17% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_v3_module module. When using HTTP/3 with OpenSSL versions <= OpenSSL 3.5.0 under certain configurations, a limited heap buffer overflow could happen while processing a TLS handshake. This can happen in a non-deterministic manner that is beyond the attacker's control. This may cause a heap buffer overflow in the NGINX worker process leading to a restart and/or limited data corruption. Impact: This vulnerability may allow remote attackers to cause a denial-of-service (DoS) on the NGINX system or limited data corruption. 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.24 | nginx | 1.30.6-r0 | ALPINE-CVE-2026-90439 |
| Debian:14 | nginx | 1.30.4-7 | DEBIAN-CVE-2026-90439 |
| Ubuntu:22.04:LTS | nginx | no fix listed | UBUNTU-CVE-2026-90439 |
| Ubuntu:24.04:LTS | nginx | no fix listed | UBUNTU-CVE-2026-90439 |
| Ubuntu:26.04:LTS | nginx | no fix listed | UBUNTU-CVE-2026-90439 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| F5 | NGINX Plus | 37.1.0.1 – before 37.1.1.237.0.0.1 – before 37.0.6.2 |
| F5 | NGINX Open Source | 1.29.2 – before 1.31.61.30.4 – before 1.30.5 |
Weakness: CWE-122 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
References
- https://my.f5.com/manage/s/article/K000162604 vendor-advisory