PatchSiren cyber security CVE debrief
CVE-2026-41847 Spring CVE debrief
A security bypass vulnerability exists in Spring WebFlux applications when using the Kotlin Router DSL. The vulnerability affects Spring Framework versions 5.3.0 through 5.3.48.
- Vendor
- Spring
- Product
- Spring Framework
- CVSS
- MEDIUM 4.8
- CISA KEV
- Not listed in stored evidence
- Original CVE published
- 2026-06-09
- Original CVE updated
- 2026-06-11
- Advisory published
- 2026-06-09
- Advisory updated
- 2026-06-11
Who should care
Users of Spring Framework versions 5.3.0 through 5.3.48 who utilize Spring WebFlux applications with the Kotlin Router DSL.
Technical summary
The vulnerability allows for a security bypass, with a CVSS score of 4.8 and a severity rating of MEDIUM. The Common Vulnerability Scoring System (CVSS) vector is CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N.
Defensive priority
MEDIUM
Recommended defensive actions
- Upgrade to Spring Framework version 5.3.49 or later.
- Refer to the vendor advisory for more information: [ref-4](https://spring.io/security/cve-2026-41847)
Evidence notes
The CVE record and details can be found at: [cve-org](https://www.cve.org/CVERecord?id=CVE-2026-41847) and [nvd](https://nvd.nist.gov/vuln/detail/CVE-2026-41847).
Sources and references
Verified primary and authoritative sources
-
CVE-2026-41847 CVE Program record
Publisher, destination, and source semantics verified
URL: https://www.cve.org/CVERecord?id=CVE-2026-41847
CVE Program - Official CVE Program record with source-provided CVE metadata.
-
CVE-2026-41847 NVD vulnerability detail
Publisher, destination, and source semantics verified
URL: https://nvd.nist.gov/vuln/detail/CVE-2026-41847
NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.
Supplemental references
-
Mitigation or vendor reference
Unverified legacy reference
URL: https://spring.io/security/cve-2026-41847
[email protected] - Vendor Advisory
Methodology and review provenance
AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.