# CVE-2021-2351: CVE-2021-2351

Status: published. Published: 2021-07-20. Updated: 2026-11-02.

Vulnerability in the Advanced Networking Option component of Oracle Database Server. Supported versions that are affected are 12.1.0.2, 12.2.0.1 and 19c. Difficult to exploit vulnerability allows unauthenticated attacker with network access via Oracle Net to compromise Advanced Networking Option. Successful attacks require human interaction from a person other than the attacker and while the vulnerability is in Advanced Networking Option, attacks may significantly impact additional products. Successful attacks of this vulnerability can result in takeover of Advanced Networking Option. Note: The July 2021 Critical Patch Update introduces a number of Native Network Encryption changes to deal with vulnerability CVE-2021-2351 and prevent the use of weaker ciphers. Customers should review: "Changes in Native Network Encryption with the July 2021 Critical Patch Update" (Doc ID 2791571.1). CVSS 3.1 Base Score 8.3 (Confidentiality, Integrity and Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H).

## Remediation

No remediation reported in collected sources

## Affected products and versions

- Oracle Corporation / WebLogic Server: 12.2.1.3.0 (affected); 12.2.1.4.0 (affected); 14.1.1.0.0 (affected). Source: CNA: oracle

## Severity and prioritization

- CVSS 3.1: 8.3 (high); CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H; source: CNA: oracle

- CISA KEV: No listing in collected sources

- EPSS: 2.43% as of 2026-11-02; percentile 84.25%

- SSVC: exploitation none; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: Not reported

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://www.oracle.com/security-alerts/cpujul2021.html (CNA: oracle; x_refsource_MISC)

- https://www.oracle.com/security-alerts/cpuoct2021.html (CNA: oracle; x_refsource_MISC)

- http://seclists.org/fulldisclosure/2021/Dec/19 (CNA: oracle; mailing-list, x_refsource_FULLDISC)

- http://seclists.org/fulldisclosure/2021/Dec/20 (CNA: oracle; mailing-list, x_refsource_FULLDISC)

- https://www.oracle.com/security-alerts/cpujan2022.html (CNA: oracle; x_refsource_MISC)

- http://packetstormsecurity.com/files/165258/Oracle-Database-Weak-NNE-Integrity-Key-Derivation.html (CNA: oracle; x_refsource_MISC)

- http://packetstormsecurity.com/files/165255/Oracle-Database-Protection-Mechanism-Bypass.html (CNA: oracle; x_refsource_MISC)

- https://www.oracle.com/security-alerts/cpuapr2022.html (CNA: oracle; x_refsource_MISC)

- https://www.oracle.com/security-alerts/cpujul2022.html (CNA: oracle; x_refsource_MISC)

- https://www.oracle.com/security-alerts/cpujan2023.html (CNA: oracle; vendor-advisory)

- https://www.oracle.com/security-alerts/cpujul2021.html (ADP: CVE; x_refsource_MISC, x_transferred)

- https://www.oracle.com/security-alerts/cpuoct2021.html (ADP: CVE; x_refsource_MISC, x_transferred)

- http://seclists.org/fulldisclosure/2021/Dec/19 (ADP: CVE; mailing-list, x_refsource_FULLDISC, x_transferred)

- http://seclists.org/fulldisclosure/2021/Dec/20 (ADP: CVE; mailing-list, x_refsource_FULLDISC, x_transferred)

- https://www.oracle.com/security-alerts/cpujan2022.html (ADP: CVE; x_refsource_MISC, x_transferred)

- http://packetstormsecurity.com/files/165258/Oracle-Database-Weak-NNE-Integrity-Key-Derivation.html (ADP: CVE; x_refsource_MISC, x_transferred)

- http://packetstormsecurity.com/files/165255/Oracle-Database-Protection-Mechanism-Bypass.html (ADP: CVE; x_refsource_MISC, x_transferred)

- https://www.oracle.com/security-alerts/cpuapr2022.html (ADP: CVE; x_refsource_MISC, x_transferred)

- https://www.oracle.com/security-alerts/cpujul2022.html (ADP: CVE; x_refsource_MISC, x_transferred)

- https://www.oracle.com/security-alerts/cpujan2023.html (ADP: CVE; vendor-advisory, x_transferred)

## Provenance

- CNA: oracle: https://www.cve.org/CVERecord?id=CVE-2021-2351; retrieved 2026-11-02; source updated 2026-11-02

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2021-2351; retrieved 2026-11-02; source updated Not reported

Revision: 7e442ab929ebc5ed804a85b3aa7b3f082f8ff017d2230d763206b9589095f692

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