CVE-2026-18511

IBM i 7.6, 7.5, 7.4, and 7.3 could allow a local authenticated attacker to generate a stack-based buffer overflow in the Native IBM i JSSE provider, caused by improper bounds checking during TLS session establishment. A local attacker could overflow a fixed-length buffer and execute arbitrary code on the system or cause the JVM process to crash.

CVSS v3 7.3 HIGH

7.3^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://www.ibm.com/support/pages/node/7283285	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:ibm:i:7.3:::::::*
	cpe:2.3:a:ibm:i:7.4:::::::*
	cpe:2.3:a:ibm:i:7.5:::::::*
	cpe:2.3:a:ibm:i:7.6:::::::*

History

No history.

Information

Published : 2026-08-13 21:17

Updated : 2026-08-17 13:25

NVD link : CVE-2026-18511

Mitre link : CVE-2026-18511

CVE.ORG link : CVE-2026-18511

JSON object : View

Products Affected

ibm

i

CWE

CWE-787

Out-of-bounds Write

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