CVE-2021-25633

LibreOffice supports digital signatures of ODF documents and macros within
documents, presenting visual aids that no alteration of the document
occurred since the last signing and that the signature is valid. An
Improper Certificate Validation vulnerability in LibreOffice allowed an
attacker to create a digitally signed ODF document, by manipulating the
documentsignatures.xml or macrosignatures.xml stream within the document to
combine multiple certificate data, which when opened caused LibreOffice to
display a validly signed indicator but whose content was unrelated to the
signature shown. This issue affects: The Document Foundation LibreOffice
7-0 versions prior to 7.0.6; 7-1 versions prior to 7.1.2.

Notes