CVE-2021-3689 json
Use of Predictable Algorithm in Random Number Generator in yiisoft/yii2
published 2021-08-10 5 y ago modified 2026-06-17 4 mo ago also GHSA-hq3v-rg6f-6hx4 , EUVD-2021-2074
- cvss
- 8.1
- version 3.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.9%
- EPSS 1.9% chance of exploitation in 30 days, percentile 79%
- public exploits
- 0
- none known
Summary
yii2 is vulnerable to Use of Predictable Algorithm in Random Number Generator
Patch / fix
Exploit prediction
1.90% chance of exploitation in the next 30 days, higher than 79% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- huntr.dev https://huntr.dev/bounties/50aad1d4-eb00-4573-b8a4-dbe38e2c229f referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.0 | 8.1 | CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N |
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:P/A:N |
| GitHub | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| packagist | yiisoft/yii2-dev | <2.0.43 |
2.0.43 |
Affected products
- yiisoft yiisoft/yii2
Classification
References
-
github.com
/yiisoft/yii2/commit/13f27e4d920a05d53236139e8b07007acd046a46
web, patch, third-party-advisory
-
huntr.dev
/bounties/50aad1d4-eb00-4573-b8a4-dbe38e2c229f
web, exploit, third-party-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2021-3689
advisory
-
github.com
/yiisoft/yii2
package
Sources
- CVE List CVE-2021-3689
- GitHub Advisory GHSA-hq3v-rg6f-6hx4
- NVD CVE-2021-3689
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.