CVE-2026-15396
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.
Does this matter?
Lower severity and a low EPSS score (0.37%). Track it; it rarely justifies an emergency change on its own.
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.
- CVSS 3.1
- 6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
- EPSS
- 0.37% probability · 30th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-444
- Source
- psirt@us.ibm.com
EPSS 0.4% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.