CVE-2021-25636

Incorrect trust validation of signature with ambiguous KeyInfo children

Description

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 contain both "X509Data" and "KeyValue" children of the "KeyInfo" tag, which when opened caused LibreOffice to verify using the "KeyValue" but to report verification with the unrelated "X509Data" value. This issue affects: The Document Foundation LibreOffice 7.2 versions prior to 7.2.5.

Categories

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.11%
Vendor Advisory fedoraproject.org Vendor Advisory libreoffice.org
Affected: The Document Foundation LibreOffice
Published at:
Updated at:

References

Link Tags
https://www.libreoffice.org/about-us/security/advisories/CVE-2021-25636/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NE6UIBCPZWRBWPSEGJOPNWPPT3CCMVH2/ vendor advisory
https://lists.debian.org/debian-lts-announce/2023/03/msg00022.html mailing list

Frequently Asked Questions

What is the severity of CVE-2021-25636?
CVE-2021-25636 has been scored as a high severity vulnerability.
How to fix CVE-2021-25636?
To fix CVE-2021-25636, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-25636 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-25636 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-25636?
CVE-2021-25636 affects The Document Foundation LibreOffice.
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