What is CVE-2025-36421?

CVE-2025-36421 is a medium-severity vulnerability in IBM Controller, classified under Cleartext Transmission of Sensitive Information. CVSS score: 5.9/10. Published 2026-09-18.

How severe is CVE-2025-36421?

Medium severity. CVSS v3 base score is 5.9 out of 10.

Vulnerability in IBM Controller

CVE-2025-36421

IBM Controller 11.0.0 through 11.0.1 FP7, and 11.1.0 through 11.1.3 FP1 transmits data in clear text that could allow an attacker to obtain sensitive information using man in the middle techniques.

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N.

Affected products

Ibm Controller

Weakness classification (CWE)

CWE-319 — Cleartext Transmission of Sensitive Information

References

psirt@us.ibm.com (vendor-advisory, patch)

Frequently asked questions

What is CVE-2025-36421?: CVE-2025-36421 is a medium-severity vulnerability in IBM Controller, classified under Cleartext Transmission of Sensitive Information. CVSS score: 5.9/10. Published 2026-09-18.
How severe is CVE-2025-36421?: Medium severity. CVSS v3 base score is 5.9 out of 10.