{"api_version":"1","generated_at":"2026-11-03T18:06:07+00:00","cve":"CVE-2026-121564","urls":{"html":"https://cve.report/CVE-2026-121564","api":"https://cve.report/api/cve/CVE-2026-121564.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-121564","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-121564"},"summary":{"title":"Silent loss of messages when merging overlapping chat exports in whatstk","description":"Incomplete Comparison with Missing Factors (CWE-1023) in merge_chats() (whatstk/utils/chat_merge.py), reached from BaseChat.merge(), in whatstk from 0.3.0 before 0.9.0 allows a party that supplies the chat exports to cause messages to be absent from the merged output with no indication that anything was removed, because the merge keeps whole the chat whose first message is oldest and appends from the other only the messages that are strictly newer than the last message of the first. 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