What is CVE-2026-9170?

CVE-2026-9170 is a critical-severity vulnerability in IBM HTTP Server, classified under Code Injection. CVSS score: 9.8/10. Published 2026-05-26.

How severe is CVE-2026-9170?

Critical severity. CVSS v3 base score is 9.8 out of 10.

RCE in IBM HTTP Server

CVE-2026-9170

IBM HTTP Server 8.5, and 9.0 is vulnerable to denial of service and a potential remote code execution due to improper input validation.

Vulnerability class: RCE (Remote Code Execution)

Published 2026-05-26 · last modified 2026-07-20.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.009 (57.8th percentile), scored 2026-10-19.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 58th percentile — 57.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.009 · change: +0.004

Affected products

IBM HTTP Server — versions 8.5, 9.0
IBM HTTP Server — versions 8.5.0.0, 9.0.0.0
IBM Web Server Plug-Ins For Websphere Application And Liberty — versions 8.5, 9.0

Weakness classification (CWE)

CWE-94 — Code Injection

References

www.ibm.com/support/pages/node/7274072 (vendor-advisory, patch)
www.ibm.com/support/pages/node/7274065 (vendor-advisory, patch, Vendor Advisory)

Frequently asked questions

What is CVE-2026-9170?: CVE-2026-9170 is a critical-severity vulnerability in IBM HTTP Server, classified under Code Injection. CVSS score: 9.8/10. Published 2026-05-26.
How severe is CVE-2026-9170?: Critical severity. CVSS v3 base score is 9.8 out of 10.