CVE-2026-5430: WSO2 Universal Gateway · Improper Validation of Certificate With Host Mismatch
Affects WSO2 Universal GatewaySource CVE Database V5
Exploited in the wild · KEV due 27 Sep 2026 · 22% EPSS : upgrade to 4.6.0.21 or 4.5.0.57 now.
Data as of 5 Nov 2026, 00:01 UTC
- KEV deadline
- US federal agencies must patch by this date; a sensible deadline for everyone else. Other KEV due dates
- EPSS
- 22.3% chance of exploitation in 30 days – higher than 97% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 4.6.0.21, 4.5.0.57, 4.5.0.56 +12
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:HExploitation evidence
t = 0 is the CVE’s publication on cve.org
Disclosed: evidence found.
CVE published 6 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: evidence found.
Public exploit code: GitHub proofs of concept
Exploited in the wildExploited: evidence found.
Listed in CISA KEV 49 days after disclosure
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
Timeline
CVE ID reserved
by WSO2 LLC
, 126 days before disclosure
CVE published
on cve.org
, t = 0
In Threat Radar
record ingested
, 38 minutes after disclosure
Added to CISA KEV (opens in a new tab)
exploitation confirmed
, 49 days after disclosure
KEV remediation due
US federal deadline
, 52 days after disclosure
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), GitHub proofs of concept, CISA KEV (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 5 Nov 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| WSO2WSO2 Universal Gateway | Affected
| Fixed in
|
| WSO2WSO2 Universal Gateway | Affected
| Fixed in
|
| WSO2WSO2 Traffic Manager | Affected
| Fixed in
|
| WSO2WSO2 Traffic Manager | Affected
| Fixed in
|
| WSO2WSO2 API Control Plane | Affected
| Fixed in
|
| WSO2WSO2 API Control Plane | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
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.