Buffer Over-read in NGINX ngx_http_scgi_module and ngx_http_uwsgi_module
CVE-2026-42946 is a high-severity vulnerability in NGINX's ngx_http_scgi_module and ngx_http_uwsgi_module. When scgi_pass or uwsgi_pass is configured, a state mismatch after an incomplete upstream status-line read can lead to cross-buffer pointer subtraction, producing an invalid key length and triggering excessive memory allocation or an over-read of data. Public descriptions indicate this can manifest as a roughly 1 TB allocation attempt or buffer over-read while processing specially crafted upstream response headers/status data. An unauthenticated attacker who can act as a man-in-the-middle and control responses from the upstream SCGI/uWSGI server may exploit the flaw against the NGINX worker process.
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Impact, mitigation & remediation
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Impact
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Mitigation
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Remediation
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Exploits
No valid public exploits. Mallory filtered out 3 candidates as fakes, detection scripts, or README-only repos.
All candidate exploits were filtered out by Mallory's validation.
Affected products & vendors
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Recent activity
14 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
A high-severity excessive memory allocation vulnerability in NGINX ngx_http_scgi_module and ngx_http_uwsgi_module that can crash worker processes.
An excessive memory allocation flaw in NGINX ngx_http_scgi_module and ngx_http_uwsgi_module that could let an adversary-in-the-middle controlling upstream responses read worker memory or force a restart.
An excessive memory allocation vulnerability in NGINX ngx_http_scgi_module and ngx_http_uwsgi_module that may allow memory disclosure or worker process restart under specific upstream-response control conditions.
An excessive memory allocation flaw in NGINX SCGI/UWSGI modules that can crash worker processes via extremely large allocations.
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Cross-references every affected SKU, including bundled OEM variants.
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