---
cve: "CVE-2026-23903"
severity: "MEDIUM"
cvss: 5.3
epss: "0.4%"
vendor: "Apache Software Foundation"
kev: false
exploited: false
published: "2026-02-09 09:26:21"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-24T21:00:11+02:00"
---

# CVE-2026-23903

> 5.3 MEDIUM

## Beschreibung

Authentication Bypass by Alternate Name vulnerability in Apache Shiro.

This issue affects Apache Shiro: before 2.0.7.

Users are recommended to upgrade to version 2.0.7, which fixes the issue.

The issue only effects static files. If static files are served from a case-insensitive filesystem,
such as default macOS setup, static files may be accessed by varying the case of the filename in the request.
If only lower-case (common default) filters are present in Shiro, they may be bypassed this way.

Shiro 2.1.0 and later has a new parameters to remediate this issue
shiro.ini: filterChainResolver.caseInsensitive = true
application.properties: shiro.caseInsensitive=true

Shiro 3.0.0 and later makes this the default in shiro.ini-based configurations.
Shiro 3.0.1 and later makes this the default in all configurations, including programmatic and Spring / Spring Boot.

## CVSS-Vektor

```
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Gering | warn |
| I Integrität | Keine | good |
| A Verfügbarkeit | Keine | good |

## Referenzen

- <https://lists.apache.org/thread/5jjf0hnjcol58z2m5y255c7scz1lnp8k>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-23903) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_