CVE-2026-5430
Authentication Bypass via JWT Algorithm Mismatch in Multiple WSO2 Products Allows Account Takeover
- Published
- Updated
- Reserved
- Assigned by
- WSO2
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.
Exploited in the wild
CISA lists this vulnerability in its Known Exploited Vulnerabilities catalog as WSO2 Multiple Products Path Traversal Vulnerability.
- Added
- 24 Sept 2026
- Fix due (US federal)
- 27 Sept 2026
- Used by ransomware
- Not known
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.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. CISA's SSVC rates its exploitation: it is being exploited.
Timeline
ID reserved
By WSO2
- 4 months later
· 4 months later
Published
- 49 days later
· 49 days later
Added to CISA KEV
Known exploited in the wild
- 1 day later
· 1 day later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| WSO2CNA (assigner) | 3.1 | Critical10.0 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
| NVDNVD · Analyzed | 3.1 | Critical10.0 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 22.4% · top 2.3% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: active · Automatable: yes · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 10.0.
Weakness
Affected products
- affected 4.5.0 – < 4.5.0.57
- affected 4.6.0 – < 4.6.0.21
- affected 4.5.0 – < 4.5.0.56
- affected 4.6.0 – < 4.6.0.21
- affected 4.5.0 – < 4.5.0.58
- affected 4.6.0 – < 4.6.0.22
- unknown < 4.1.0
- affected 4.1.0 – < 4.1.0.257
- affected 4.2.0 – < 4.2.0.197
- affected 4.3.0 – < 4.3.0.108
- affected 4.4.0 – < 4.4.0.72
- affected 4.5.0 – < 4.5.0.57
- affected 4.6.0 – < 4.6.0.21
WSO2 · WSO2 Carbon API Manager Rest API Utility
- affected 9.20.74 – < 9.20.74.401
- affected 9.28.116 – < 9.28.116.417
- affected 9.29.120 – < 9.29.120.236
- affected 9.30.67 – < 9.30.67.167
- affected 9.31.86 – < 9.31.86.158
- affected 9.32.147 – < 9.32.147.59
- unaffected 9.33.106 – ≤ *
What to do
Solution: Follow the instructions given on https://security.docs.wso2.com/en/latest/security-announcements/security-advisories/2026/WSO2-2026-5328/#solution https://security.docs.wso2.com/en/latest/security-announcements/security-advisories/2026/WSO2-2026-5328/#solution
References (2)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- CISA KEV catalog (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-5430)Record last updated .