Description
Hedera Guardian through 3.5.1 contains an authentication bypass vulnerability in the GET /api/v1/demo/registered-users endpoint that allows unauthenticated attackers to retrieve sensitive user information. Attackers can access the endpoint without providing authentication credentials to obtain usernames, Hedera DIDs, parent registry DIDs, system roles, and policy role assignments for all registered users in the system.
Affected products
hedera: guardian
References2
- github.com/hashgraph/guardian/pull/6076 Issue TrackingPatch
- www.vulncheck.com/advisories/hedera-guardian-authentication-byp… Third Party Advisory
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - CVSS 4.0
-
6.9
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 30 · as of 14 November 2026
- CWE
- CWE-306
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.