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TI-2026-03785 Aliases CVE-2026-4349GHSA-46qm-5mvh-mmxr

Duende IdentityServer4 Token Renewal Endpoint authorize improper authentication

Priority LOW 28CWE-287Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Attack requirements
None
Impact type
Security bypass
Confidentiality · integrity · availability
Low · Low · Low
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-287.

Summary

A vulnerability was determined in Duende IdentityServer4 up to 4.1.2. The affected element is an unknown function of the file /connect/authorize of the component Token Renewal Endpoint. This manipulation of the argument id_token_hint causes improper authentication. It is possible to initiate the attack remotely. The attack is considered to have high complexity. The exploitability is described as difficult. This vulnerability only affects products that are no longer supported by the maintainer.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00432 37th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
DuendeIdentityServer44.1.0; 4.1.1; 4.1.2—No fix listedCNA
  • IdentityServer4 VendorDuende Affected 4.1.0; 4.1.1; 4.1.2 Fixed in — No fix listed CNA

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-4349
  2. 2026-10-03 Alias added: GHSA-46qm-5mvh-mmxr

References

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Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences