What’s Vulnerable › Vulnerabilities

CVE-2026-15634: IBM WebSphere Application Server and IBM WebSphere Application Server - Liberty Request Smuggling

• Severity: medium (CVSS 6.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-09-14 · updated 2026-10-22
• Weakness: CWE-444

Description

IBM WebSphere Application Server 8.5 and 9.0, and IBM WebSphere Application Server - Liberty 17.0.0.3 through 26.0.0.8 are vulnerable to HTTP request smuggling, caused by improper parsing of the HTTP transfer-encoding request header. By sending a specially crafted HTTP transfer-encoding request header, an attacker could exploit this vulnerability to poison the web cache, bypass web application firewall protection, and conduct XSS attacks.

Affected products

• IBM WebSphere Application Server: from 17.0.0.3 through 26.0.0.5; 9.0, 8.5

References

• https://www.ibm.com/support/pages/node/7286610
• https://www.ibm.com/support/pages/node/7286611

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