Denial of Service and Wildcard Query Vulnerability in IBM API Connect
CVE-2026-18535

9.6CRITICAL

Key Information:

Vendor

IBM
Status
Api Connect
Vendor
CVE Published:
7 November 2026

What is CVE-2026-18535?

IBM API Connect versions 10.0.8.0 to 10.0.8.12 and 12.1.0.0 to 12.1.1.2 are susceptible to a Regular Expression Denial of Service (ReDoS) attack. This vulnerability stems from an improper handling of wildcard query operators, which can lead to performance degradation and potential service outages. Attackers may exploit this weakness to send specially crafted requests that cause the application to hang or crash, impacting service availability.

Affected Version(s)

API Connect 12.1.0.0 <= 12.1.1.2

API Connect 10.0.8.0 <= 10.0.8.12

References

https://www.ibm.com/support/pages/node/7291753
vendor-advisorypatch
https://www.ibm.com/support/pages/node/7292434
vendor-advisorypatch

CVSS V3.1

Score:
9.6
Severity:
CRITICAL
Confidentiality:
High
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Changed

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.