CVE-2026-23903
5.3 · MEDIUMOverview
CVE-2026-23903 is a medium-severity vulnerability affecting apache shiro. It was published on February 9, 2026 and has a CVSS 3.1 base score of 5.3 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 5.3, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
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.
Remediation
Check the references section for vendor advisories and patches from apache. Update shiro to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| apache | shiro | >= 0, < 2.0.7 | Affected |
Frequently Asked Questions
What is CVE-2026-23903?
CVE-2026-23903 is a medium-severity vulnerability affecting apache shiro. It was published on February 9, 2026 and has a CVSS 3.1 base score of 5.3 (MEDIUM).
How severe is CVE-2026-23903?
This vulnerability has a CVSS 3.1 base score of 5.3, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-23903?
Check the references section for vendor advisories and patches from apache. Update shiro to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-23903?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-23903 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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