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QUIC-LEAK (CVE-2025-54939) is a memory-leak vulnerability in the LiteSpeed QUIC (LSQUIC) library before version 4.3.1. The flaw occurs in the lsquic_engine_packet_in packet-input function, which leaks memory while processing packets.
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1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos.
Repository is a small, runnable PoC for QUIC-LEAK (CVE-2025-54939), a pre-handshake memory exhaustion/memory leak in LSQUIC (affecting LSQUIC < 4.3.1 and LiteSpeed/OpenLiteSpeed versions listed in README). Structure: (1) docker-compose.yml + .env provide a local lab with OpenLiteSpeed (ports 80, 443 TCP and 443/udp for QUIC, plus 7080 admin) and supporting services (MariaDB, Redis, phpMyAdmin). (2) poc/poc.py is the exploit: it crafts minimal QUIC v1 long-header packets (Initial plus many Handshake packets) and sends them via UDP to a specified host/port in an infinite loop, aiming to trigger the vulnerable pre-handshake code path (lsquic_engine_packet_in) repeatedly. (3) poc/entrypoint.sh launches 15 concurrent Python processes targeting the docker service name 'litespeed' on port 443 to accelerate memory exhaustion. No post-exploitation is present; the sole capability is remote DoS against a QUIC-enabled vulnerable endpoint.
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Cross-references every affected SKU, including bundled OEM variants.
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