CVE-2021-3523

mediumpriority · track · 30EPSS 0.008 · 58 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.85% (58th) EPSS

CVSS 4.3 · medium

Is it mine?

2 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

A flaw was found in 3Scale APICast in versions prior to 2.11.0, where it incorrectly identified connections for reuse. This flaw allows an attacker to bypass security restrictions for an API request when hosting multiple APIs on the same IP address.

cvss

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

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.3–7.5

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 8.6 · 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

v3.16.9mediumCVSS: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-281USprimary

affected products (2)

Products and version ranges known to be affected.

n/a apicast≤ 3scale-apicast versions prior to 2.11.0enisa_euvdEU
redhat apicast< 2.11.0nvdUScpe:2.3:a:redhat:apicast:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2022-04-27modified 2026-06-17

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references (5)

External citations — patches, advisories, analysis.

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