Details have been revealed about three vulnerabilities in the LibreOffice and Apache OpenOffice office suites, allowing attackers to prepare documents that appear to be signed by a trusted source or to change the date of an already signed document. The issues were resolved in the Apache OpenOffice 4.1.11 and LibreOffice 7.0.6/7.1.2 releases, disguised as unrelated bugs (the LibreOffice 7.0.6 and 7.1.2 releases were published in early May, but details of the vulnerabilities were only disclosed now).
- CVE-2021-41832, CVE-2021-25635 — allows an attacker to sign an ODF document with an untrusted self-signed certificate, but by changing the digital signature algorithm to an incorrect or unsupported value, cause this document to be displayed as trustworthy (the signature with the incorrect algorithm was treated as valid).
- CVE-2021-41830, CVE-2021-25633 — allows an attacker, by combining data signed by different certificates in the documentsignatures.xml and macrosignatures.xml files, to create an ODF document or macro that will display as trustworthy in the interface, despite containing additional content certified by another certificate.
- CVE-2021-41831, CVE-2021-25634 — allows modifications to be made to a signed ODF document that distort the displayed time of the digital signature's creation without violating trust indications.
Bron: opennet.ru
