CVE-2021-3689

mediumpriority · track · 31OT risk · elevatedEPSS 0.019 · 80 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.90% (80th) EPSS

CVSS 5 · medium

Is it mine?

3 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · nvd · osv

EPSS · scored 2026-10-24

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

cvss

Technical severity, 0–10. One row per scoring source.

8.1

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–8.1

v2.05mediumAV:N/AC:L/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.08.1highCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · ENISA EU

v3.08.1highCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · security@huntr.devexploitability 2.2 · impact 5.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:Nsecondary · OSV

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-330USprimaryCWE-1241USCWE-330US

affected products (3)

Products and version ranges known to be affected.

yiisoft yiisoft/yii2≤ unspecified ≤2.0.42.1enisa_euvdEU
yiiframework yii2.0.0 → 2.0.43nvdUScpe:2.3:a:yiiframework:yii:*:*:*:*:*:*:*:*
Packagist yiisoft/yii2-dev< 2.0.43osvUSpkg:composer/yiisoft/yii2-dev

advisories (1)

Vendor and ecosystem advisories describing this.

GHSA-hq3v-rg6f-6hx4Use of Insufficiently Random Values in yiisoft/yii2-dev2021-09-01ghsa · osvUS
yii2 is vulnerable to Use of Predictable Algorithm in Random Number Generator

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd osv NVD CVE.org MITRE

published 2021-08-10modified 2026-06-17

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references (6)

External citations — patches, advisories, analysis.

scry

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