---
cve: "CVE-2026-31837"
severity: "HIGH"
cvss: 8.7
epss: "38%"
vendor: "istio"
kev: false
exploited: false
published: "2026-03-10 22:16:21"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-15T09:30:09+02:00"
---

# CVE-2026-31837

> 8.7 HIGH · 🧪 PoC

## Beschreibung

Istio is an open platform to connect, manage, and secure microservices. Prior to 1.29.1, 1.28.5, and 1.27.8, a user of Istio is impacted if the JWKS resolver becomes unavailable or the fetch fails, exposing hardcoded defaults regardless of use of the RequestAuthentication resource. This vulnerability is fixed in 1.29.1, 1.28.5, and 1.27.8.

## CVSS-Vektor

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

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

## Patch verfügbar (OSV)

- 4aee98e195c1af3f5e9385c637050db22d8c41d8 (Commit)
- 7da6662175184479cb9281f3d814d6994bf1009f (Commit)

## Referenzen

- <https://github.com/istio/istio/security/advisories/GHSA-v75c-crr9-733c>
- <https://access.redhat.com/errata/RHSA-2026:10184>
- <https://access.redhat.com/errata/RHSA-2026:5948>
- <https://access.redhat.com/errata/RHSA-2026:5950>
- <https://access.redhat.com/errata/RHSA-2026:5952>
- <https://access.redhat.com/security/cve/CVE-2026-31837>
- <https://bugzilla.redhat.com/show_bug.cgi?id=2446344>
- <https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-31837.json>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-31837) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_