Medium severity · published Mar 21, 2025
CVE-2021-25635
An Improper Certificate Validation vulnerability in LibreOffice allowed an attacker to self sign an ODF document, with a signature untrusted by the target, then modify it to…
5.5
CVSS
0.1%
EPSS
No
On KEV
Description
An Improper Certificate Validation vulnerability in LibreOffice allowed
an attacker to self sign an ODF document, with a signature untrusted by
the target, then modify it to change the signature algorithm to an
invalid (or unknown to LibreOffice) algorithm and LibreOffice would incorrectly present such a signature with an unknown algorithm as a
valid signature issued by a trusted person
This issue affects LibreOffice: from 7.0 before 7.0.5, from 7.1 before 7.1.1.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 3% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
Libreoffice · Libreoffice
7.0.0 before 7.0.5.1; 7.1.0.0 through 7.1.1.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-25635
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-25635
Vendor Advisory
https://www.libreoffice.org/about-us/security/advisories/cve-2021-25635/
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