{"cve":"CVE-2021-25636","nvd":{"published":"2022-02-24T15:15:21.813","modified":"2026-06-17T03:42:15.550","status":"Modified","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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","score":7.5},"cwes":["CWE-295","CWE-347"],"references":["https://lists.debian.org/debian-lts-announce/2023/03/msg00022.html","https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NE6UIBCPZWRBWPSEGJOPNWPPT3CCMVH2/","https://www.libreoffice.org/about-us/security/advisories/CVE-2021-25636/","https://lists.debian.org/debian-lts-announce/2023/03/msg00022.html","https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NE6UIBCPZWRBWPSEGJOPNWPPT3CCMVH2/"],"products":["fedoraproject:fedora","libreoffice:libreoffice"],"source":"nvd","synced_at":"2026-10-19T21:28:04.509275555+00:00"},"epss":{"cve":"CVE-2021-25636","score":0.00954,"percentile":0.61374,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}