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IBM disclosed a critical CVE-2026-8633 vulnerability in WebSphere Application Server and WebSphere Liberty deployments that use the optional Web Server Plug-ins component, warning that unauthenticated attackers can send specially crafted HTTP requests to execute arbitrary commands on the host. The flaw, classified as improper control of code generation (CWE-94) and rated CVSS 9.8, affects WebSphere Application Server traditional and Liberty versions 8.5 and 9.0, with successful exploitation potentially leading to full system compromise.
IBM also patched CVE-2026-8620, an HTTP request smuggling issue that could let attackers bypass security controls and manipulate backend communications in affected environments. The company said both issues are addressed through APAR PH71342 and related fix packs, and advised administrators to apply the fixes, validate updates in non-production environments, monitor HTTP traffic, restrict exposure of plug-in endpoints, use WAF protections, and perform threat hunting for signs of exploitation.
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IBM said the disclosed vulnerabilities are addressed by APAR PH71342 and recommended applying the relevant interim fixes or upgrading to the minimum fixed levels. The company also advised administrators to test updates before production deployment and take defensive measures such as monitoring HTTP traffic and restricting plug-in exposure.
IBM issued a security bulletin for WebSphere Application Server and WebSphere Liberty deployments using optional Web Server Plug-ins, disclosing CVE-2026-8633, a critical unauthenticated remote code execution flaw, and CVE-2026-8620, an HTTP request smuggling issue. IBM said the vulnerabilities affect versions 8.5 and 9.0 and provided remediation guidance.
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IBM disclosed multiple vulnerabilities in the optional **Web Server Plug-ins** used with **WebSphere Application Server** and **WebSphere Liberty**, including **CVE-2026-8633**, a critical unauthenticated code injection flaw rated **CVSS 9.8**, and **CVE-2026-8620**, an **HTTP request smuggling** issue rated **CVSS 7.5**. The bugs affect supported **8.5** and **9.0** plug-in branches that sit in front of back-end WebSphere servers on platforms including Apache HTTP Server, Microsoft IIS, and IBM HTTP Server, allowing specially crafted HTTP requests to bypass trust boundaries, reach internal application servers, and potentially achieve arbitrary code execution and full system compromise. IBM said **no workarounds or mitigations are available** and directed customers to apply interim fixes or upgrade to fixed plug-in versions tied to **APAR PH71342**, later updated under **PH71376**. IBM support notices said fixes were released through Fix Central for affected **9.0.5.24-9.0.5.27** and **8.5.5.25-8.5.5.29** ranges, with permanent remediation targeted for inclusion in **WebSphere Application Server 9.0.5.28** and **8.5.5.30**. The combined disclosure raised concern that request smuggling could help attackers bypass perimeter controls before exploiting the RCE flaw in exposed enterprise deployments.
Jul 12, 2026
IBM disclosed multiple vulnerabilities in **WebSphere Application Server** and **WebSphere Application Server Liberty**, including denial-of-service issues tracked as `CVE-2026-9071` and `CVE-2026-9320`, and an HTTP request smuggling flaw, `CVE-2026-8646`, rated up to **CVSS 8.1**. The affected products include WebSphere Application Server **8.5** and **9.0**, along with WebSphere Liberty versions **17.0.0.3 through 26.0.0.6** when certain servlet or websocket features are enabled. IBM said no workarounds or mitigations are available and advised customers to apply interim fixes for **APAR PH71631** and **PH71370** or upgrade to fix packs **26.0.0.7**, **9.0.5.29**, or **8.5.5.30**. A related high-severity issue, `CVE-2026-9072`, affects **IBM i 7.3 through 7.6** in environments using WebSphere Application Server or Liberty with **Intelligent Management** and the **WebSphere WebServer Plug-in**. IBM said an attacker who can impersonate backend servers and send crafted responses to the plug-in could trigger **remote code execution** and **denial of service**, also with a **CVSS 8.1** rating. Recommended actions include installing the latest WebSphere security updates, updating IBM i to current levels, and reviewing the secure configuration of Intelligent Management and the WebSphere WebServer Plug-in.
Jun 29, 2026
IBM disclosed two vulnerabilities in traditional **IBM WebSphere Application Server** affecting versions **9.0** and **8.5**, led by **CVE-2026-14512**, a **pre-authentication unsafe deserialization** flaw rated **CVSS 9.8**. The issue could allow a remote attacker to **bypass authentication** or achieve **arbitrary code execution** without user interaction, creating a high-risk path to full compromise of exposed WebSphere environments. IBM also identified **CVE-2026-14528**, a **CVSS 7.4** flaw that could expose sensitive information through insertion into log files. The company directed customers to apply the interim fix for **APAR PH72166** or upgrade to **Fix Pack 9.0.5.29+** for WebSphere 9.0 and **Fix Pack 8.5.5.31+** for WebSphere 8.5, and said **no workarounds or mitigations are available**.
Jul 29, 2026