Quick answers
- Is CVE-2026-18535 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-18535 being exploited in the wild.
- How severe is CVE-2026-18535?
- Critical severity, with a CVSS score of 9.6, published 7 November 2026.
- Which products and versions are affected?
- IBM API Connect 10.0.8.0 through 10.0.8.12, 12.1.0.0 through 12.1.1.2.
- Is there a fix for CVE-2026-18535?
- Yes: fixed in IBM API Connect 10.0.8.13, 12.1.1.3. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-18535 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-18535?
- Check whether you run IBM API Connect at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- Fixed in: IBM API Connect 10.0.8.13, 12.1.1.3
Technical details
The vulnerability is a regular expression denial of service (ReDoS) affecting IBM API Connect in the specified version ranges. An attacker can craft malicious input that causes a regular expression evaluation to consume excessive CPU resources, resulting in denial of service. The attack vector is network-based with no authentication required.
Affected products
- IBM API Connect 10.0.8.0 through 10.0.8.12, 12.1.0.0 through 12.1.1.2
Timeline
- 2026-11-07: disclosed