CVE-2026-18020: CWE-125 Out-of-bounds Read
CVE-2026-18020 is an out-of-bounds read vulnerability (CWE-125) affecting IBM i versions 7.3, 7.4, 7.5, and 7.6. The flaw is caused by an off-by-one error in bounds checking, which could be exploited by a remote attacker to cause a denial of service. The vulnerability does not impact confidentiality or integrity but can affect availability. The CVSS score is 5.3, indicating a medium severity level. No official patch or remediation guidance is currently available from the vendor. There are no known exploits in the wild at this time.
AI Analysis
Technical Summary
IBM i versions 7.3 through 7.6 contain an off-by-one error in bounds checking that leads to an out-of-bounds read (CWE-125). This vulnerability allows a remote attacker to cause a denial of service condition by triggering this error. The vulnerability affects system availability but does not compromise confidentiality or integrity. The CVSS v3.1 base score is 5.3 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L). No vendor advisory or patch information is currently available, and no known exploits have been reported.
Potential Impact
A remote attacker can cause a denial of service on affected IBM i systems due to an off-by-one bounds checking error resulting in an out-of-bounds read. There is no impact on confidentiality or integrity. The availability impact is limited to denial of service conditions.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, monitor IBM security advisories for updates. No specific mitigations are provided by the vendor at this time.
CVE-2026-18020: CWE-125 Out-of-bounds Read
Description
CVE-2026-18020 is an out-of-bounds read vulnerability (CWE-125) affecting IBM i versions 7.3, 7.4, 7.5, and 7.6. The flaw is caused by an off-by-one error in bounds checking, which could be exploited by a remote attacker to cause a denial of service. The vulnerability does not impact confidentiality or integrity but can affect availability. The CVSS score is 5.3, indicating a medium severity level. No official patch or remediation guidance is currently available from the vendor. There are no known exploits in the wild at this time.
CVSS v3.1
Score 5.3medium
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 off-by-one error in bounds checking that leads to an out-of-bounds read (CWE-125). This vulnerability allows a remote attacker to cause a denial of service condition by triggering this error. The vulnerability affects system availability but does not compromise confidentiality or integrity. The CVSS v3.1 base score is 5.3 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L). No vendor advisory or patch information is currently available, and no known exploits have been reported.
Potential Impact
A remote attacker can cause a denial of service on affected IBM i systems due to an off-by-one bounds checking error resulting in an out-of-bounds read. There is no impact on confidentiality or integrity. The availability impact is limited to denial of service conditions.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, monitor IBM security advisories for updates. No specific mitigations are provided by the vendor at this time.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- ibm
- Date Reserved
- 2026-07-27T23:56:18.399Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6a7e2fb1bf8831d539cb5ca6
Added to database: 08/13/2026, 20:57:21 UTC
Last enriched: 08/21/2026, 13:30:33 UTC
Last updated: 09/28/2026, 13:47:42 UTC
Views: 47
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