What’s Vulnerable › Vulnerabilities

CVE-2021-3689: Use of Predictable Algorithm in Random Number Generator in yiisoft/yii2

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.9% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2021-08-10 · updated 2026-06-17
• Weakness: CWE-1241

Description

yii2 is vulnerable to Use of Predictable Algorithm in Random Number Generator

Affected products

• yiisoft yii: from 2.0.0 before 2.0.43 — fixed in 2.0.43

How to fix

Upgrade to a fixed version: yiisoft yii 2.0.43. Check the vendor advisory for mitigations.

References

• https://github.com/yiisoft/yii2/commit/13f27e4d920a05d53236139e8b07007acd046a46
• https://huntr.dev/bounties/50aad1d4-eb00-4573-b8a4-dbe38e2c229f
• https://github.com/yiisoft/yii2/commit/13f27e4d920a05d53236139e8b07007acd046a46
• https://huntr.dev/bounties/50aad1d4-eb00-4573-b8a4-dbe38e2c229f

Get alerted when CVE-2021-3689 or the next vulnerability affects your stack