High severity · published Dec 22, 2023
CVE-2023-50714
The Oauth2 PKCE implementation is vulnerable
8.8
CVSS
0.5%
EPSS
No
On KEV
Description
yii2-authclient is an extension that adds OpenID, OAuth, OAuth2 and OpenId Connect consumers for the Yii framework 2.0. In yii2-authclient prior to version 2.2.15, the Oauth2 PKCE implementation is vulnerable in 2 ways. First, the `authCodeVerifier` should be removed after usage (similar to `authState`). Second, there is a risk for a `downgrade attack` if PKCE is being relied on for CSRF protection. Version 2.2.15 contains a patch for the issue. No known workarounds are available.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 42% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
YI
yii2-authclient · yiisoft
< 2.2.15 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-50714
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-50714
Product
https://github.com/yiisoft/yii2-authclient/blob/0d1c3880f4d79e20aa1d77c012650b54e69695ff/src/OAuth1.php#L158
Product
https://github.com/yiisoft/yii2-authclient/blob/0d1c3880f4d79e20aa1d77c012650b54e69695ff/src/OAuth2.php#L121
Product
https://github.com/yiisoft/yii2-authclient/blob/0d1c3880f4d79e20aa1d77c012650b54e69695ff/src/OpenIdConnect.php#L420
Patch
https://github.com/yiisoft/yii2-authclient/commit/721ed974bc44137437b0cdc8454e137fff8db213
Exploit
https://github.com/yiisoft/yii2-authclient/security/advisories/GHSA-rw54-6826-c8j5
More from yii2-authclient
9.8
CVE-2023-50708
yii2-authclient vulnerable to possible timing attack on string comparison in OAuth1, OAuth2 and OpenID Connect implementation