Read the docs
TI-2020-08927 Aliases CVE-2020-11053GHSA-j7px-6hwj-hpjg

Open Redirect in OAuth2 Proxy

Priority LOW 33CWE-601Published · Updated

Key facts

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

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

Summary

In OAuth2 Proxy before 5.1.1, there is an open redirect vulnerability. Users can provide a redirect address for the proxy to send the authenticated user to at the end of the authentication flow. This is expected to be the original URL that the user was trying to access. This redirect URL is checked within the proxy and validated before redirecting the user to prevent malicious actors providing redirects to potentially harmful sites. However, by crafting a redirect URL with HTML encoded whitespace characters the validation could be bypassed and allow a redirect to any URL provided. This has been patched in 5.1.1.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0079 56th percentileScored 2026-11-07
Fix Fixed OAuth2 Proxy (OAuth2 Proxy): 5.1.1github.com/oauth2-proxy/oauth2-proxy (Go): 5.1.1

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
oauth2-proxyOAuth2 Proxybefore 5.1.15.1.1Patch availableCNA
—github.com/oauth2-proxy/oauth2-proxy (Go)before 5.1.15.1.1Patch availableGHSA-j7px-6hwj-hpjg
  • OAuth2 Proxy Vendoroauth2-proxy Affected before 5.1.1 Fixed in 5.1.1 Patch available CNA
  • github.com/oauth2-proxy/oauth2-proxy (Go) Vendor— Affected before 5.1.1 Fixed in 5.1.1 Patch available GHSA-j7px-6hwj-hpjg

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:oauth2_proxy_project:oauth2_proxy:*:*:*:*:*:*:*:*before 5.1.1Vulnerableoauth2-proxy
  • cpe:2.3:a:oauth2_proxy_project:oauth2_proxy:*:*:*:*:*:*:*:* Versions before 5.1.1 Vulnerable ·oauth2-proxy

Remediation

  • Fix · CNA OAuth2 Proxy (OAuth2 Proxy) Fixed in 5.1.1
  • Fix · GHSA-j7px-6hwj-hpjg github.com/oauth2-proxy/oauth2-proxy (Go) Fixed in 5.1.1 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-11053
  2. 2026-10-03 Alias added: GHSA-j7px-6hwj-hpjg

References

Advisory 2

Other 1

  • TI-2025-34353 OAuth2-Proxy has authentication bypass in oauth2-proxy skip_auth_routes due to Query Parameter inclusion CVSS 3.1CRITICAL 9.1
  • TI-2026-29315 OAuth2 Proxy has an Authentication Bypass via X-Forwarded-Uri Header Spoofing CVSS 3.1CRITICAL 9.1
  • TI-2026-26722 OAuth2 Proxy: Health Check User-Agent Matching Bypasses Authentication in auth_request Mode CVSS 3.1CRITICAL 9.1
  • TI-2026-29698 OAuth2 Proxy has an Authentication Bypass via Fragment Confusion in skip_auth_routes and skip_auth_regex CVSS 3.1HIGH 8.2
  • TI-2017-14408 CSRF in Bitly oauth2_proxy 2.1 during authentication flow CVSS 3.0HIGH 8.8
  • TI-2026-29314 OAuth2 Proxy has an Authorization Bypass in Email Domain Validation via Malformed Multi-@ Email Claims CVSS 3.1MEDIUM 6.8
See all 12 →

Sources

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