{"schemaVersion":3,"id":"CVE-2026-53524","aliases":["UBUNTU-CVE-2026-53524","DEBIAN-CVE-2026-53524"],"status":"published","duplicateOf":null,"title":null,"description":"WeeChat (Wee Enhanced Environment for Chat) is a free chat client. In versions 4.3.0 through 4.9.0, the WeeChat relay module's WebSocket permessage-deflate decompression function relay_websocket_inflate() has no upper bound on output size. An authenticated relay user can send a small compressed WebSocket frame (~100 bytes) that decompresses to gigabytes, exhausting all server memory and crashing the entire WeeChat process. The api protocol enables permessage-deflate and requires authentication before WebSocket upgrade. 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