Cyber Resilience

CVE-2026-8620

HighUpdated

Published: 26 May 2026

Published
26 May 2026
Modified
02 June 2026
KEV Added
Patch
CVSS Score v3.1 7.5 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:L/A:N
EPSS Score 0.0023 13.9th percentile
Risk Priority 15 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-8620 is a high-severity HTTP Request/Response Smuggling (CWE-444) vulnerability in Ibm Websphere Application Server. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 13.9th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

IBM Web Server Plug-ins for WebSphere Application Server and WebSphere Liberty 8.5, 9.0 IBM WebSphere Application Server and WebSphere Application Server Liberty are vulnerable to HTTP request smuggling in the Web Server Plug-ins through a specially crafted request.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Why these techniques?

HTTP request smuggling vulnerability in public-facing WebSphere web server plug-in directly enables exploitation of the application via crafted requests (CWE-444).

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

CVEs Like This One

CVE-2026-8644Same product: Ibm Websphere Application Server
CVE-2026-9319Same product: Ibm Websphere Application Server
CVE-2026-9311Same product: Ibm Websphere Application Server
CVE-2025-14914Same product: Ibm Websphere Application Server
CVE-2026-9330Same product: Ibm Websphere Application Server
CVE-2026-8633Same product: Ibm Websphere Application Server
CVE-2026-3621Same product: Ibm Websphere Application Server
CVE-2025-14923Same product: Ibm Websphere Application Server
CVE-2026-3366Same vendor: Ibm
CVE-2024-41787Same vendor: Ibm

Affected Assets

ibm
websphere application server
8.5.0.0 — 8.5.5.30 · 8.5.0.0 — 8.5.5.30 · 9.0.0.0 — 9.0.5.28

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References