CVE-2021-23435

Open Redirect

MEDIUM
6.1
CVSS Score
Published: September 12, 2021 at 08:05 PM UTC
Updated: June 17, 2026 at 03:38 AM UTC
1 product affected across 1 vendorClearance

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Severity
MEDIUM6.1
Exploit prediction
EPSS 0.7%

Description

This affects the package clearance before 2.5.0. The vulnerability can be possible when users are able to set the value of session[:return_to]. If the value used for return_to contains multiple leading slashes (/////example.com) the user ends up being redirected to the external domain that comes after the slashes (http://example.com).

Affected

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

v < 2.5.0
Affected range stops below 2.5.0, 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:

References (2)

x_refsource_MISCPatchThird Party Advisory
https://github.com/thoughtbot/clearance/pull/945
x_refsource_MISCThird Party Advisory
https://snyk.io/vuln/SNYK-RUBY-CLEARANCE-1577284

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

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