CVE-2021-41832Network attack vector

Document signature forgery via certificate validation flaw

Published Oct 11, 2021 · Updated Aug 4, 2024

Apache OpenOffice 4.1.10 and earlier contain an improper signature-verification flaw that lets remote attackers make altered documents appear trusted. The certificate-validation logic accepts an untrusted digital signature as trusted while permitting ODF content changes without invalidating the signature. Exploitation requires delivery and opening of a crafted document; the demonstrated impact is document-integrity deception, with no reported confidentiality or service interruption.

CVSS severity7.5
High
EPSS probability1.34%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Apache OpenOffice 4.1.10 and earlier contain an improper signature-verification flaw that lets remote attackers make altered documents appear trusted. The certificate-validation logic accepts an untrusted digital signature as trusted while permitting ODF content changes without invalidating the signature. Exploitation requires delivery and opening of a crafted document; the demonstrated impact is document-integrity deception, with no reported confidentiality or service interruption.

The record

CVE
CVE-2021-41832
Published
Oct 11, 2021
Updated
Aug 4, 2024
Vendor
The Apache Software Foundation
Product
Apache OpenOffice
Classifications
CWE-347, T1036
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 11, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=Apache OpenOffice <=4.1.10
  2. Affected versionversion=OpenOffice.org <=3.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Apache Software Foundation · Apache OpenOfficeversion=Apache OpenOffice <=4.1.10; version=OpenOffice.org <=3.4

Published CVSS scores

5.0NVDAV:N/AC:L/Au:N/C:N/I:P/A:N
7.5NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-347Improper Verification of Cryptographic Signature
T1036Masquerading

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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