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TI-2020-12005 Aliases CVE-2020-15233GHSA-rfq3-w54c-f9q5

OAuth2 Redirect URL validity does not respect query parameters and character casing for loopback addresses

Priority LOW 29CWE-20Published · Updated

Key facts

Attack vector
Network
Privileges required
High
User interaction
Required
Attack complexity
Low
Impact type
Spoofing
Confidentiality · integrity · availability
High · High · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-601.

Summary

ORY Fosite is a security first OAuth2 & OpenID Connect framework for Go. In Fosite from version 0.30.2 and before version 0.34.1, there is an issue in which an an attacker can override the registered redirect URL by performing an OAuth flow and requesting a redirect URL that is to the loopback adapter. Attackers can provide both custom URL query parameters to their loopback redirect URL, as well as actually overriding the host of the registered redirect URL. These attacks are only applicable in scenarios where the attacker has access over the loopback interface. This vulnerability has been patched in ORY Fosite v0.34.1.

Why it matters now

EPSS 0.008 56th percentileScored 2026-11-07
Fix Fixed fosite (ory): 0.34.1github.com/ory/fosite (Go): 0.34.1

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
oryfositebefore 0.34.10.34.1Patch availableCNA
—github.com/ory/fosite (Go)0.30.3 to before 0.34.10.34.1Patch availableGHSA-rfq3-w54c-f9q5
  • fosite Vendorory Affected before 0.34.1 Fixed in 0.34.1 Patch available CNA
  • github.com/ory/fosite (Go) Vendor— Affected 0.30.3 to before 0.34.1 Fixed in 0.34.1 Patch available GHSA-rfq3-w54c-f9q5

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:ory:fosite:*:*:*:*:*:*:*:*0.30.2 to before 0.34.1Vulnerableory
  • cpe:2.3:a:ory:fosite:*:*:*:*:*:*:*:* Versions 0.30.2 to before 0.34.1 Vulnerable ·ory

Remediation

  • Fix · CNA fosite (ory) Fixed in 0.34.1
  • Fix · GHSA-rfq3-w54c-f9q5 github.com/ory/fosite (Go) Fixed in 0.34.1 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-15233
  2. 2026-10-03 Alias added: GHSA-rfq3-w54c-f9q5

References

Patch 1

Advisory 2

Other 2

  • TI-2020-11995 Ignored storage errors on token revokation in ORY Fosite CVSS 3.1HIGH 8.0
  • TI-2020-11994 Replay of private_key_jwt possible in ORY Fosite CVSS 3.1HIGH 8.1
  • TI-2020-12006 Redirect URL matching ignores character casing CVSS 3.1MEDIUM 6.1

Sources

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