{"schemaVersion":3,"id":"CVE-2026-25961","aliases":[],"status":"published","duplicateOf":null,"title":null,"description":"SumatraPDF is a multi-format reader for Windows. In 3.5.0 through 3.5.2, SumatraPDF's update mechanism disables TLS hostname verification (INTERNET_FLAG_IGNORE_CERT_CN_INVALID) and executes installers without signature checks. 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