CVE-2026-18221: CWE-287 Improper Authentication
Description
CVE-2026-18221 is a high-severity vulnerability affecting IBM i versions 7.3, 7.4, 7.5, and 7.6. It involves improper authentication due to insufficient validation of client-supplied authentication parameters, potentially allowing remote attackers unauthorized access.
CVSS v3.1
Score 8.1high
Affected software
IBM
cpe:2.3:a:ibm:i:7.6:*:*:*:*:*:*:*cpe:2.3:a:ibm:i:7.6.0:*:*:*:*:*:*:*cpe:2.3:a:ibm:i:7.5:*:*:*:*:*:*:*cpe:2.3:a:ibm:i:7.5.0:*:*:*:*:*:*:*cpe:2.3:a:ibm:i:7.4:*:*:*:*:*:*:*cpe:2.3:a:ibm:i:7.4.0:*:*:*:*:*:*:*Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
IBM i versions 7.3 through 7.6 contain an improper authentication vulnerability (CWE-287) where client-supplied authentication parameters are not properly validated. This flaw could allow a remote attacker to gain unauthorized access to the system. The vulnerability has a CVSS 3.1 base score of 8.1, indicating high severity with network attack vector, high attack complexity, no privileges required, no user interaction, and impacts confidentiality, integrity, and availability.
Potential Impact
Successful exploitation could lead to unauthorized remote access with full confidentiality, integrity, and availability impact on the affected IBM i systems. This means attackers could potentially read, modify, or disrupt system operations.
Mitigation Recommendations
No explicit patch or remediation information is provided in the available data. Patch status is not yet confirmed — check the IBM vendor advisory for current remediation guidance. Until an official fix is available, restrict network access to affected systems and monitor for suspicious authentication attempts.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- ibm
- Date Reserved
- 2026-07-29T10:16:45.385Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6a9af3e1acd9273b49e2f96b
Added to database: 09/04/2026, 16:37:53 UTC
Last enriched: 09/15/2026, 00:55:05 UTC
Last updated: 10/17/2026, 18:48:17 UTC
Views: 82
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