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Fencer Vulns
high 7.5

CVE-2021-25634 json

Timestamp Manipulation with Signature Wrapping

published 2021-10-12 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-12530

cvss
7.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.7%
EPSS 0.7% chance of exploitation in 30 days, percentile 53%
public exploits
0
none known

Summary

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 modify a digitally signed ODF document to insert an additional signing time timestamp which LibreOffice would incorrectly present as a valid signature signed at the bogus signing time. This issue affects: The Document Foundation LibreOffice 7-0 versions prior to 7.0.6; 7-1 versions prior to 7.1.2.

Patch / fix

  • The Document Foundation LibreOffice 7.0.6, 7.1.2
  • libreoffice Debian 14, Debian 13, Debian 12 1:7.2.0-2

debian advisories DEBIAN-CVE-2021-25634

  • libreoffice Ubuntu 20.04 LTS 1:6.4.7-0ubuntu0.20.04.2

ubuntu advisories UBUNTU-CVE-2021-25634

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • libreoffice RHEL 8 1:6.4.7.2-10.el8
  • autocorr-af RHEL 8 1:6.4.7.2-10.el8
  • autocorr-bg RHEL 8 1:6.4.7.2-10.el8
  • autocorr-ca RHEL 8 1:6.4.7.2-10.el8
  • autocorr-cs RHEL 8 1:6.4.7.2-10.el8
  • autocorr-da RHEL 8 1:6.4.7.2-10.el8
  • autocorr-de RHEL 8 1:6.4.7.2-10.el8
  • autocorr-en RHEL 8 1:6.4.7.2-10.el8

red hat advisories RHSA-2022:1766

  • autocorr-af AlmaLinux 8 1:6.4.7.2-10.el8.alma
  • autocorr-bg AlmaLinux 8 1:6.4.7.2-10.el8.alma
  • autocorr-ca AlmaLinux 8 1:6.4.7.2-10.el8.alma
  • autocorr-cs AlmaLinux 8 1:6.4.7.2-10.el8.alma
  • autocorr-da AlmaLinux 8 1:6.4.7.2-10.el8.alma
  • autocorr-de AlmaLinux 8 1:6.4.7.2-10.el8.alma
  • autocorr-en AlmaLinux 8 1:6.4.7.2-10.el8.alma
  • autocorr-es AlmaLinux 8 1:6.4.7.2-10.el8.alma

almalinux advisories ALSA-2022:1766

  • libreoffice Rocky Linux 8 1:6.4.7.2-10.el8

rocky linux advisories RLSA-2022:1766

  • libreoffice Alpine 3.24, Alpine 3.23, Alpine 3.22 +7 more 7.2.2.2-r0

alpine advisories ALPINE-CVE-2021-25634

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2021-25634 updated cvss 7.1

libreoffice: Timestamp Manipulation with Signature Wrapping

  • Red Hat Enterprise Linux 6 autocorr-af, autocorr-bg, autocorr-ca, autocorr-cs, autocorr-da, autocorr-de, +60 more Red Hat Enterprise Linux 7 autocorr-af, autocorr-bg, autocorr-ca, autocorr-cs, autocorr-da, autocorr-de, +105 more
    affected: no fix planned “Out of support scope”
  • Red Hat Enterprise Linux 8 autocorr-af, autocorr-bg, autocorr-ca, autocorr-cs, autocorr-da, autocorr-de, +98 more
    affected: no fix planned “Will not fix”
  • Red Hat Enterprise Linux AppStream (v. 8) autocorr-af 6.4.7.2-10.el8, autocorr-bg 6.4.7.2-10.el8, autocorr-ca 6.4.7.2-10.el8, autocorr-cs 6.4.7.2-10.el8, autocorr-da 6.4.7.2-10.el8, autocorr-de 6.4.7.2-10.el8, +95 more Red Hat Enterprise Linux CRB (v. 8) libreoffice-sdk 6.4.7.2-10.el8
    fixed: vendor fix RHSA-2022:1766
  • Red Hat Enterprise Linux 9 autocorr-af, autocorr-bg, autocorr-ca, autocorr-cs, autocorr-da, autocorr-de, +101 more
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

0.71% chance of exploitation in the next 30 days, higher than 53% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
NVD 2.0 5.0 AV:N/AC:L/Au:N/C:N/I:P/A:N

Affected products

  • The Document Foundation LibreOffice

Classification

Weakness
  • CWE-295 Improper Certificate Validation

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.