CVE-2026-15396mediumCWE-444

CVE-2026-15396: medium-severity vulnerability in IBM WebSphere Application Server

IBM WebSphere Application Server IBM WebSphere Application Server - Liberty HTTP Request Smuggling

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 6.5epss 0.4%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Affected products
IBM · WebSphere Application ServerIBM · WebSphere Application Server - Liberty
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