Use-after-Free in NGINX ngx_http_v3_module HTTP/3 QPACK Processing
CVE-2026-42530 is a critical use-after-free vulnerability in the NGINX Open Source ngx_http_v3_module. The flaw is reachable when NGINX is configured to use the HTTP/3 QUIC module. A remote, unauthenticated attacker can send a specially crafted HTTP/3 session that reopens a QPACK encoder stream, triggering a use-after-free condition in the NGINX worker process. This results in memory corruption in the worker handling the connection. The issue affects the HTTP/3 processing path in NGINX Open Source, with reported affected versions including 1.31.0 and 1.31.1, and it is fixed in 1.31.2. End-of-Technical-Support versions were not evaluated.
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Recent activity
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A critical use-after-free vulnerability in the ngx_http_v3_module of NGINX Open Source that can be exploited remotely without authentication via a crafted HTTP/3 session, potentially causing denial of service or arbitrary code execution under certain conditions.
A high-severity memory corruption vulnerability in the NGINX ngx_http_v3_module that could potentially enable remote code execution or service disruption.
A critical unauthenticated vulnerability in NGINX HTTP modules that can trigger a use-after-free, causing worker process restart and potentially arbitrary code execution if ASLR is disabled or bypassed.
A critical NGINX vulnerability in ngx_http_v3_module that can be exploited by unauthenticated remote attackers to cause DoS or potentially achieve code execution on vulnerable systems with non-default configurations.
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Cross-references every affected SKU, including bundled OEM variants.
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