CVE-2026-8620Network attack vector

Unauthenticated HTTP request smuggling

Published May 26, 2026 · Updated May 26, 2026

HTTP request smuggling in IBM Web Server Plug-ins 8.5 and 9.0 allows remote attackers to read and alter traffic via crafted requests. IBM has not published the parser locus or the exact inconsistency used when the plug-in and front-end web server interpret a request. The optional plug-in must be installed and network-reachable; exploitation requires high-complexity conditions and does not interrupt service.

CVSS severity7.5
High
EPSS probability0.28%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

HTTP request smuggling in IBM Web Server Plug-ins 8.5 and 9.0 allows remote attackers to read and alter traffic via crafted requests. IBM has not published the parser locus or the exact inconsistency used when the plug-in and front-end web server interpret a request. The optional plug-in must be installed and network-reachable; exploitation requires high-complexity conditions and does not interrupt service.

The record

CVE
CVE-2026-8620
Published
May 26, 2026
Updated
May 26, 2026
Vendor
OpenBMC Project
Product
Web Server Plug-ins for IBM WebSphere Application Server
Classifications
CWE-444, 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, 9.0 <=Interim Fix 002

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

OpenBMC Project · Web Server Plug-ins for IBM WebSphere Application Serverversion=8.5, 9.0 <=Interim Fix 002

Published CVSS scores

7.5IBMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:L/A:N

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-444Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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