Critical severity · published May 26, 2026
CVE-2026-8855
IBM HTTP Server is affected by multiple vulnerabilities
9.8
CVSS
0.5%
EPSS
No
On KEV
Description
IBM HTTP Server 8.5, and 9.0 is vulnerable to remote code execution and denial of service in configurations with TLS mutual authentication (client authentication).
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 40% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
HS
HTTP Server · IBM
8.5.0 through Interim Fix 002; 9.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-8855
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-8855
Vendor Advisory
https://www.ibm.com/support/pages/node/7274065
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