CVE-2021-3523
A flaw was found in 3Scale APICast in versions prior to 2.11.0, where it incorrectly identified...
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
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.
- Record
CVE-2021-3523- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - CVSS 2.0
- 4.3 Medium
AV:N/AC:M/Au:N/C:N/I:P/A:N - Weakness
- CWE-281
- Updated
- 2026-11-02
CVE List No score
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.
- Record
CVE-2021-3523- Weakness
- CWE-281
- Updated
- 2026-11-02
EUVDEUVD-2021-26839 No score
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.
- Record
EUVD-2021-26839- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-wxqh-rqgc-pfr9
A flaw was found in 3Scale APICast in versions prior to 2.11.0, where it incorrectly identified...
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.
- Record
GHSA-wxqh-rqgc-pfr9- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-281
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-3523 is a high vulnerability (CVSS 7.5) in Redhat Apicast, published April 27, 2022. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.85%, the 58th percentile. No source names a fixed version.