CVE-2020-11053

Open Redirect in OAuth2 Proxy

MEDIUM
6.1
CVSS Score
Published: May 7, 2020 at 08:30 PM UTC
Updated: June 17, 2026 at 02:48 AM UTC
2 products affected across 2 vendorsOAUTH2 ProxyOAuth2 Proxy

Using OAuth2 Proxy by OAuth2 Proxy?

Get instant alerts when new vulnerabilities affect OAuth2 Proxy - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
MEDIUM6.1
Exploit prediction
EPSS 0.8%
SSVC
No known exploit

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 5.1.1
Affected range stops below 5.1.1, so it looks safe — our inference, not a vendor statement
v < 5.1.1
Affected range stops below 5.1.1, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-601

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card