An Improper Certificate Validation vulnerability in LibreOffice allowed an attacker to modify a digitally signed ODF document to insert an additional signing time timestamp which LibreOffice would incorrectly present as a valid signature signed at the bogus signing time.
RHEL 8.6.0 and below are all affected by this flaw. RHEL 9 uses an updated version which is not exposed to the flaw. LibreOffice allowed for the ability to insert a signing timestamp which allowed for LibreOffice to show a valid signature due to the altered signing time.
This issue has been addressed in the following products: Red Hat Enterprise Linux 8 Via RHSA-2022:1766 https://access.redhat.com/errata/RHSA-2022:1766
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s): https://access.redhat.com/security/cve/cve-2021-25634