SB2026082505 - Red Hat Enterprise Linux 8 update for the nginx:1.24 module
Published: August 25, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 2 vulnerabilities.
1) Use-after-free (CVE-ID: CVE-2026-56434)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 8.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to cause a denial of service or modify memory contents.
The vulnerability exists due to use-after-free in the ngx_http_ssi_module module when processing responses from an upstream server with SSI enabled, proxy_pass configured, and proxy_buffering disabled. A remote attacker can control responses from an upstream server to cause a denial of service or modify memory contents.
Exploitation requires man-in-the-middle ability over upstream server responses. This is a data plane issue only.
2) Use of uninitialized resource (CVE-ID: CVE-2026-60005)
CWE-ID: CWE-908 - Use of Uninitialized Resource
CVSSv4: 8.8 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to disclose limited memory contents or cause a denial of service.
The vulnerability exists due to use of an uninitialized resource in ngx_http_slice_module when handling requests with the slice directive and unnamed regex captures configured or during a background cache update. A remote attacker can send crafted requests to disclose limited memory contents or cause a denial of service.
The issue affects the NGINX worker process and is limited to the data plane. The module is not enabled by default and must be built with the --with-http_slice_module configuration parameter.
Remediation
Install update from vendor's website.