CVE-2021-25635: libreoffice Cert Validation Flaw — Fix

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.

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CVSS v3.1 Score

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

Weakness Type (CWE)

CWE-295 CWE-295

Affected Products

Vendor	Product	Versions
libreoffice	libreoffice	7.0.0 — 7.0.5.1
libreoffice	libreoffice	7.1.0.0 — 7.1.1.1

References

Advisories & Patches

https://www.libreoffice.org/about-us/security/advisories/cve-2021-25635/

Frequently Asked Questions

What is 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. It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2021-25635? +

CVE-2021-25635 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2021-25635? +

CVE-2021-25635 affects products from libreoffice, specifically: libreoffice. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2021-25635? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2021-25635