CVE-2026-18511 IBM i is Affected By Multiple Vulnerabilities in Java Secure Sockets Extension
A local authenticated attacker can exploit a stack-based buffer overflow in the IBM i JSSE provider to execute arbitrary code or crash the JVM.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-18511?
CVE-2026-18511 is a high-severity memory corruption vulnerability in Ibm I, published on 13 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-787
Which versions are affected by CVE-2026-18511?
It affects 1 product.
Products include Ibm I.
How do I fix CVE-2026-18511?
No fix has been published for CVE-2026-18511 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-18511 being exploited?
There is no known exploitation of CVE-2026-18511 in the wild and no public exploit code.
Other vulnerabilities in Ibm I
- CVE-2026-96119 IBM i is Affected By An Improper Control of Code Generation Vulnerability in HTTP Server Administration GUI
- CVE-2026-16860 IBM i is Affected By Remote Code Execution Vulnerability []
- CVE-2026-17083 IBM i is Affected By Multiple Vulnerabilities in the Debug Server
- CVE-2026-17218 IBM i is Affected By Remote Code Execution Vulnerability in Line Printer Daemon []
- CVE-2026-17276 IBM i is Affected By Multiple Vulnerabilities in Navigator for i
Sources
Also known as GHSA-7484-cp4g-hrj6.