Vulnerability · Published Jun 22, 2026 · Assigned by ibm

CVE-2026-8858WebSphere Application Server Remote Code Execution

High 7.5

In plain English

A high-severity code injection in WebSphere Application Server from IBM. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 35% of all known vulnerabilities).

Severity (CVSS 3.1)7.5High

Exploit odds (30 days)0.4%top 64.6% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

IBM WebSphere Application Server and IBM WebSphere Application Server Liberty are vulnerable to remote code execution and denial of service in the WebSphere Web Server Plug-in component. This vulnerability can be exploited when an attacker impersonates the application server and sends crafted responses to the plug-in.

Affected products (as reported)

Vendor	Product	Versions
IBM	WebSphere Application Server	8.59.0

Weakness: CWE-94 · Vector: CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

References

https://www.ibm.com/support/pages/node/7276560 vendor-advisory, patch