SB2026090730 - Multiple vulnerabilities in IBM App Connect Enterprise
Published: September 7, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 2 vulnerabilities.
1) Missing Release of Resource after Effective Lifetime (CVE-ID: CVE-2026-64607)
CWE-ID: CWE-772 - Missing Release of Resource after Effective Lifetime
CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to improper resource management in the classic i/o model HttpClient connection handling when processing a response with an invalid or unsupported content-encoding header value. A remote attacker can send a response with an invalid or unsupported content-encoding header value to cause a denial of service.
Only the classic i/o model is affected; the async i/o model is not affected.
2) Improper validation of certificate with host mismatch (CVE-ID: CVE-2026-71290)
CWE-ID: CWE-297 - Improper Validation of Certificate with Host Mismatch
CVSSv4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to impersonate the server.
The vulnerability exists due to improper certificate validation in the async transport of HttpClient when establishing TLS connections with HostnameVerificationPolicy#BUILTIN. A remote attacker can intercept and modify traffic and present a valid certificate for a different domain to impersonate the server.
The classic version of HttpClient is not affected.
Remediation
Install update from vendor's website.