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 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 v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://www.libreoffice.org/about-us/security/advisories/cve-2021-25635/	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:libreoffice:libreoffice::::::::
	cpe:2.3:a:libreoffice:libreoffice::::::::

History

10 Dec 2025, 19:18

Type	Values Removed	Values Added
CPE		cpe:2.3:a:libreoffice:libreoffice::::::::
References	~~() https://www.libreoffice.org/about-us/security/advisories/cve-2021-25635/ -~~	() https://www.libreoffice.org/about-us/security/advisories/cve-2021-25635/ - Vendor Advisory
Summary		(es) Una vulnerabilidad de validación de certificado incorrecta en LibreOffice permitió a un atacante autofirmar un documento ODF, con una firma que no era de confianza para el destino, y luego modificarlo para cambiar el algoritmo de firma a uno no válido (o desconocido para LibreOffice) y LibreOffice presentaría incorrectamente dicha firma con un algoritmo desconocido como una firma válida emitida por una persona confiable. Este problema afecta a LibreOffice: desde 7.0 antes de 7.0.5, desde 7.1 antes de 7.1.1.
First Time		Libreoffice libreoffice Libreoffice
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.5

21 Mar 2025, 15:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2025-03-21 15:15

Updated : 2025-12-10 19:18

NVD link : CVE-2021-25635

Mitre link : CVE-2021-25635

CVE.ORG link : CVE-2021-25635

JSON object : View

Products Affected

libreoffice

libreoffice

CWE

CWE-295

Improper Certificate Validation

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