CVE-2026-15396CWE-444

CVE-2026-15396

Medium · published September 15, 2026

CVSS v3.1
6.5
EPSS
0%
Percentile
15.7
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
6.5 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
CVSS v4.0
Not supplied
EPSS
0.00252 · 15.7th percentile
Weakness
CWE-444 · Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
Published
2026-09-15T00:16Z
References (2)
https://www.ibm.com/support/pages/node/7286610 · [email protected]https://www.ibm.com/support/pages/node/7286611 · [email protected]
EPSS history
Timeline
  • 16 SEP 04:25Z
    EPSS moved — → 0%
    epss
  • 14 SEP 20:08Z
    IBM WebSphere Application Server prior to 9.0.5.29 and 8.5.5.31 are affected by multiple vulnerabilities
    cvelistv5