Use-after-Free in NGINX ngx_http_v3_module HTTP/3 QPACK handling
CVE-2026-42530 is a use-after-free vulnerability in NGINX Open Source's ngx_http_v3_module, specifically in the HTTP/3 QUIC processing path. 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 mid-session. This can trigger a use-after-free condition in the NGINX worker process, resulting in memory corruption. The issue affects NGINX Open Source 1.31.0 and 1.31.1; public reporting indicates it was fixed in 1.31.2. The flaw can crash and restart the worker process and, on systems where ASLR is disabled or can be bypassed, may be leveraged for code execution.
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Exploits
No valid public exploits. Mallory filtered out 4 candidates as fakes, detection scripts, or README-only repos.
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Recent activity
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A critical use-after-free vulnerability in NGINX's ngx_http_v3_module / HTTP/3 QUIC implementation that can be triggered remotely by an unauthenticated attacker, causing denial of service and potentially arbitrary code execution in less-hardened environments.
A critical use-after-free memory corruption vulnerability in NGINX HTTP/3/QPACK handling that can cause worker crashes and potentially remote code execution under favorable conditions such as ASLR being disabled or bypassed.
A critical use-after-free in NGINX HTTP/3/QPACK handling within ngx_http_v3_module that can cause worker crashes and potentially remote code execution.
A critical use-after-free vulnerability in NGINX's ngx_http_v3_module affecting HTTP/3 QUIC-enabled servers, primarily causing denial of service via worker process restart, with possible code execution if ASLR is disabled or bypassed.
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