{"schemaVersion":3,"id":"CVE-2026-63381","aliases":["UBUNTU-CVE-2026-63381","DEBIAN-CVE-2026-63381"],"status":"published","duplicateOf":null,"title":null,"description":"Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent has a use-after-free in buffer.c when evbuffer_add_buffer_reference processes an output buffer whose out_total_len is zero. evbuffer_free_all_chains frees the initial empty chain without resetting outbuf->first, outbuf->last, or outbuf->last_with_datap, and APPEND_CHAIN_MULTICAST subsequently dereferences the dangling chain pointer. A caller that can drive this buffer state can cause memory corruption or a process crash. 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