Cloudanix VulnDB

CVE-2021-25633

High · 7.5

CVSS

7.5

EPSS

0.7%

Published

Oct 11, 2021

CISA due date

—

Cloudanix analysis

Schedule a fix SSVC: Track

Attackers can create documents that appear to have valid digital signatures even though the content has been changed or is unrelated to the signature shown.

Exploitation
Remote Unauthenticated
Attacker needs
None
Complexity
Low
Impact
Data Tampering
Component
Application
Class
Cryptographic Weakness
Remediation
Upgrade
Effort
Medium
Patch risk
Low

What it actually does

Improper Certificate Validation allows manipulation of documentsignatures.xml or macrosignatures.xml streams to combine multiple certificate data, causing the application to display a validly signed indicator for document content unrelated to the shown signature.

Why it matters to the business

Users may be tricked into trusting and acting on tampered documents presented as authentically signed, increasing risk of accepting altered files in workflows that rely on digital signatures; low ecosystem prevalence limits broad exposure but still affects document-heavy operations.

How an attack unfolds

An attacker crafts a digitally signed ODF document, manipulates the signature XML streams to merge certificate data from multiple sources, and distributes the file so that opening it displays a false valid signature indicator while the actual content differs from what was signed.

How to fix it

Upgrade LibreOffice 7-0 to 7.0.6 or later and 7-1 to 7.1.2 or later; for imagemagick/imagemagick apply commit 9caa8b0c4269163def2ce0fa6ff1754ec0c234d2; for identitypython/pysaml2 apply commit bbcbef30105a0bc6679378cdc7f04fb350259498.

How to confirm the fix worked

Confirm installed versions meet or exceed the listed fixed releases; test by opening a sample manipulated ODF document and verifying that the signature indicator correctly reflects content mismatch or invalidity.

Typical attack path

  1. Craft or obtain an ODF document
  2. Manipulate documentsignatures.xml or macrosignatures.xml to combine certificate entries
  3. Apply or reuse a valid signature structure
  4. Distribute the altered document to targets
  5. Rely on the application displaying a misleading valid signature status

How to detect it

Inspect application logs and document processing events for unexpected signature validation successes on files with mismatched content; review any available signature XML streams in forensic analysis of suspect ODF files.

What your security team should do

  • Prioritize upgrades to the specified fixed versions within standard patch windows
  • Review document signing workflows for reliance on visual signature indicators alone
  • Monitor for any downstream dependents of affected packages and apply patches accordingly

The record

LibreOffice supports digital signatures of ODF documents and macros within documents, presenting visual aids that no alteration of the document occurred since the last signing and that the signature is valid. An Improper Certificate Validation vulnerability in LibreOffice allowed an attacker to create a digitally signed ODF document, by manipulating the documentsignatures.xml or macrosignatures.xml stream within the document to combine multiple certificate data, which when opened caused LibreOffice to display a validly signed indicator but whose content was unrelated to the signature shown. This issue affects: The Document Foundation LibreOffice 7-0 versions prior to 7.0.6; 7-1 versions prior to 7.1.2.

Affected packages

Ecosystem Package Introduced Fixed
AlmaLinux:8 autocorr-af 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-bg 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-ca 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-cs 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-da 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-de 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-en 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-es 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-fa 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-fi 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-fr 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-ga 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-hr 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-hu 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-is 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-it 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-ja 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-ko 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-lb 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-lt 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-mn 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-nl 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-pl 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-pt 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-ro 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-ru 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-sk 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-sl 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-sr 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-sv 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-tr 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-vi 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 autocorr-zh 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-base 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-calc 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-core 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-data 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-draw 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-emailmerge 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-filters 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-gdb-debug-support 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-graphicfilter 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-gtk3 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-ar 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-bg 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-bn 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-ca 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-cs 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-da 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-de 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-dz 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-el 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-en 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-es 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-et 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-eu 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-fi 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-fr 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-gl 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-gu 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-he 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-hi 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-hr 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-hu 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-id 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-it 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-ja 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-ko 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-lt 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-lv 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-nb 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-nl 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-nn 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-pl 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-pt-BR 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-pt-PT 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-ro 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-ru 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-si 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-sk 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-sl 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-sv 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-ta 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-tr 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-uk 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-zh-Hans 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-help-zh-Hant 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-impress 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-af 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-ar 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-as 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-bg 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-bn 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-br 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-ca 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-cs 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-cy 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-da 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-de 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-dz 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-el 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-en 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-es 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-et 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-eu 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-fa 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-fi 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-fr 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-ga 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-gl 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-gu 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-he 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-hi 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-hr 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-hu 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-id 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-it 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-ja 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-kk 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-kn 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-ko 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-lt 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-lv 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-mai 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-ml 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-mr 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-nb 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-nl 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-nn 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-nr 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-nso 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-or 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-pa 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-pl 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-pt-BR 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-pt-PT 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-ro 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-ru 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-si 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-sk 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-sl 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-sr 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-ss 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-st 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-sv 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-ta 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-te 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-th 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-tn 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-tr 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-ts 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-uk 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-ve 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-xh 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-zh-Hans 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-zh-Hant 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-langpack-zu 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-math 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-ogltrans 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-opensymbol-fonts 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-pdfimport 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-pyuno 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-sdk 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-sdk-doc 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-ure 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-ure-common 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-wiki-publisher 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-writer 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-x11 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreoffice-xsltfilter 0 1:6.4.7.2-10.el8.alma
AlmaLinux:8 libreofficekit 0 1:6.4.7.2-10.el8.alma
Debian:11 libreoffice 0 1:7.0.4-4+deb11u1
Debian:12 libreoffice 0 1:7.2.0-2
Debian:13 libreoffice 0 1:7.2.0-2
Mageia:8 libneon 0 0.31.2-1.mga8
Mageia:8 libreoffice 0 7.2.2.2-1.mga8
Red Hat:enterprise_linux:8::appstream autocorr-af 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-bg 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-ca 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-cs 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-da 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-de 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-en 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-es 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-fa 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-fi 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-fr 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-ga 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-hr 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-hu 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-is 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-it 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-ja 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-ko 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-lb 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-lt 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-mn 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-nl 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-pl 0 1:6.4.7.2-10.el8
Red Hat:enterprise_linux:8::appstream autocorr-pt 0 1:6.4.7.2-10.el8

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