Use-after-Free in NGINX ngx_http_v3_module HTTP/3/QPACK Processing
CVE-2026-42530 is a use-after-free vulnerability in NGINX Open Source's ngx_http_v3_module when the server 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. The flaw affects HTTP/3 processing and can cause the worker process to restart. Under conditions where Address Space Layout Randomization (ASLR) is disabled, or where the attacker can otherwise bypass ASLR, the memory corruption may be leveraged for code execution.
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Impact
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Exploits
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Recent activity
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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.
A critical use-after-free vulnerability in NGINX Open Source ngx_http_v3_module affecting HTTP/3 QUIC handling, which can lead to worker process restart and potentially remote code execution under certain ASLR-related conditions.
A use-after-free vulnerability in nginx HTTP/3 handling that can be triggered via crafted QUIC/HTTP/3 traffic, with high severity and potential remote compromise impact.
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