CVE-2026-80431

The kitty terminal (versions 0.40.0 to before 0.49.0 ) contains an out-of-bounds write vulnerability in the natural width branch of the text sizing protocol. The root cause is located in screen_handle_multicell_command() within kitty/screen.c, where the application appends codepoints to a fixed-s...

CVE-2026-80431 Out-of-bounds write in the kitty text sizing protocol allows termination of the terminal process

Out-of-bounds Write in the natural width branch of the text sizing protocol in kitty from 0.40.0 before 0.49.0 allows a program writing to the terminal to write past the end of a fixed-size buffer, because screenhandlemulticellcommand in kitty/screen.c appends each codepoint of a grapheme cluster...