CVE-2026-8855Network attack vector

Unauthenticated remote code execution and service interruption

Published May 26, 2026 · Updated May 26, 2026

Code injection in IBM HTTP Server 8.5 and 9.0 allows remote attackers to execute code or crash the server through TLS client authentication. IBM has not disclosed the affected component or the operation that improperly generates code from untrusted input. Exposure requires SSLClientAuth to have a value other than 0 or None, enabling TLS mutual authentication; successful exploitation permits code execution or a server crash.

CVSS severity8.1
High
EPSS probability0.46%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Code injection in IBM HTTP Server 8.5 and 9.0 allows remote attackers to execute code or crash the server through TLS client authentication. IBM has not disclosed the affected component or the operation that improperly generates code from untrusted input. Exposure requires SSLClientAuth to have a value other than 0 or None, enabling TLS mutual authentication; successful exploitation permits code execution or a server crash.

The record

CVE
CVE-2026-8855
Published
May 26, 2026
Updated
May 26, 2026
Vendor
OpenBMC Project
Product
IBM HTTP Server
Classifications
CWE-94, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 26, 2026CVE publishedPublication date reported by the CVE source.
  2. May 26, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=8.5.0 <=Interim Fix 002
  2. Affected versionversion=9.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

OpenBMC Project · IBM HTTP Serverversion=8.5.0 <=Interim Fix 002; version=9.0

Published CVSS scores

8.1IBM CorporationCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-94Improper Control of Generation of Code ('Code Injection')
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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