CVE-2026-56434 (GCVE-0-2026-56434)
Vulnerability from cvelistv5
Published
2026-07-15 14:33
Modified
2026-07-15 18:10
Severity ?
6.5 (Medium) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H
8.3 (High) - 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
CWE
Summary
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_ssi_module module. This vulnerability may exist when the Server-Side Includes (SSI), proxy_pass, and proxy_buffering off directives are configured. With this configuration, an unauthenticated attacker with man-in-the-middle (MITM) ability to control responses from an upstream server may be able to cause a use-after-free in the NGINX worker process. This issue may lead to limited modification of memory or a restart of the NGINX worker process. Impact: This vulnerability may allow remote attackers to have limited control to modify memory contents or restart the NGINX worker process. There is no control plane exposure; this is a data plane issue only. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
References
Impacted products
Vendor Product Version
F5 NGINX Plus Version: 37.0.0.1   < 37.0.3.1
Version: R36   < R36 P7
Version: R33   < *
 Create a notification for this product.
   F5 NGINX Open Source Version: 1.31.2   < 1.31.3
Version: 0.8.11   < 1.30.4
 Create a notification for this product.
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