# CVE-2026-5430: Authentication Bypass via JWT Algorithm Mismatch in Multiple WSO2 Products Allows Account Takeover

> CVE-2026-5430: Authentication Bypass via JWT Algorithm Mismatch in Multiple WSO2 Products Allows Account Takeover. CVSS 10.0 (CVSS 3.1), in CISA KEV.

Canonical: https://rewindex.com/cve/CVE-2026-5430
Last updated: 2026-09-25T12:53:05Z

- Published: 2026-08-06 07:33 UTC · Updated: 2026-09-25 12:53 UTC · Assigner: WSO2
- CVSS: 10.0 (CVSS 3.1) · Severity: Critical · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
- EPSS: 22.4%, 98th percentile (scored 2026-10-25)
- CISA KEV: yes, added 2026-09-24, federal due date 2026-09-27, ransomware use: Unknown
- CWE: CWE-347

## Description

The JWT authentication mechanism accepts tokens signed with algorithms other than those explicitly configured or supported. This allows an attacker to craft a JWT with an unsupported algorithm, which is then incorrectly validated, leading to unauthorized access. Successful exploitation of this vulnerability may result in unauthorized access to the system, including the potential compromise of administrative accounts and full account takeover. The CVSS score is adjusted to 9.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H) in single-tenant deployments, reflecting that the impact is contained within a single security authority boundary.

## CISA required action

Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

## Affected vendors and products

- WSO2: WSO2 API Control Plane
- WSO2: WSO2 API Manager
- WSO2: WSO2 Carbon API Manager Rest API Utility
- WSO2: WSO2 Traffic Manager
- WSO2: WSO2 Universal Gateway

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-5430)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-5430)
- [https://security.docs.wso2.com/en/latest/security-announcements/security-advisories/2026/WSO2-2026-5328/](https://security.docs.wso2.com/en/latest/security-announcements/security-advisories/2026/WSO2-2026-5328/)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-5430 · Markdown: https://rewindex.com/cve/CVE-2026-5430.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-5430 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:14:30.900Z