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The Oauth2 PKCE implementation is vulnerable

Moderate
samdark published GHSA-rw54-6826-c8j5 Dec 16, 2023

Package

composer yiisoft/yii2-authclient (Composer)

Affected versions

<=2.2.14

Patched versions

2.2.15

Description

Impact

What kind of vulnerability is it? Who is impacted?

Original Report:

The Oauth2 PKCE implementation is vulnerable in 2 ways:

  1. The authCodeVerifier should be removed after usage (similar to 'authState')
  2. There is a risk for a "downgrade attack" if PKCE is being relied on for CSRF protection.

Patches

Has the problem been patched? What versions should users upgrade to?

TBD

Workarounds

Is there a way for users to fix or remediate the vulnerability without upgrading?

not known yet.

References

Are there any links users can visit to find out more?

Severity

Moderate

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
High
Privileges required
None
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N

CVE ID

CVE-2023-50714

Weaknesses

No CWEs

Credits