{"schemaVersion":3,"id":"CVE-2026-63383","aliases":["UBUNTU-CVE-2026-63383","DEBIAN-CVE-2026-63383"],"status":"published","duplicateOf":null,"title":null,"description":"Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent can read beyond a contiguous evbuffer region in event_tagging.c when decode_tag_internal requests at most five bytes from evbuffer_pullup but iterates using the full logical buffer length. A fragmented evbuffer containing a six-byte malformed tag can therefore advance past the pullup window and trigger an out-of-bounds read, which can crash a process that decodes attacker-controlled tagged RPC data. 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