---
cve: "CVE-2026-8711"
severity: "CRITICAL"
cvss: 9.2
epss: "89%"
vendor: "F5"
kev: false
exploited: false
published: "2026-05-19 15:16:33"
tags: [cve, security, critical]
source: tsecurity.de CVE-Dossier
exported: "2026-09-07T18:55:49+02:00"
---

# CVE-2026-8711

> 9.2 CRITICAL

## Beschreibung

NGINX JavaScript has a vulnerability when the js_fetch_proxy directive is configured with at least one client-controlled NGINX variable (for example, $http_*, $arg_*, $cookie_*) and a location invoking the ngx.fetch() operation from NGINX JavaScript. An unauthenticated attacker can exploit this vulnerability by sending crafted HTTP requests. This may cause a heap buffer overflow in the NGINX worker process leading to a restart. Additionally, attackers can execute code on systems with Address Space Layout Randomization (ASLR) disabled or when the attacker can bypass ASLR. 


Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

## CVSS-Vektor

```
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Hoch | good |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |

## Patch verfügbar (OSV)

- 9ead4e71f74a27279f3212bdb6cadb0e86981a1b (Commit)

## Referenzen

- <https://my.f5.com/manage/s/article/K000161307>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-8711) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_