{"schemaVersion":3,"id":"CVE-2026-77641","aliases":["UBUNTU-CVE-2026-77641","DEBIAN-CVE-2026-77641"],"status":"published","duplicateOf":null,"title":null,"description":"tor before 0.4.9.9 was prone to a NULL write after free when sending a CONFLUX_SWITCH cell fails. The return value of relay_send_command_from_edge() was   ignored, so a send failure (which calls circuit_mark_for_close()  and removes the leg via cfx_del_leg()) would go undetected, causing the caller to write to the now-freed current leg and resulting in a crash. 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