CyberSecBulletin
CVE-2024-5261NVD status: Analyzed

LibreOffice: Improper Certificate Validation

Published Updated By the CyberSecBulletin desk

CVE-2024-5261 is a critical-severity improper certificate validation vulnerability in LibreOffice from The Document Foundation, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 24.2.4 as the first without the flaw, so updating LibreOffice to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.43% chance of exploitation within 30 days, which is low compared with other CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Update LibreOffice to 24.2.4 or a later version.
  2. Update libreoffice to 24.2.4 or a later version.
  3. Read the advisory on libreoffice.org for workarounds and exact fixed builds.
  4. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
The Document FoundationLibreOffice24.2 up to, but not including, 24.2.424.2.4
Libreofficelibreofficebefore 24.2.424.2.4

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 4.010.0CriticalCNA (documentfoundation.org)
CVSS 3.19.8CriticalNVD

Official description

Improper Certificate Validation vulnerability in LibreOffice "LibreOfficeKit" mode disables TLS certification verification LibreOfficeKit can be used for accessing LibreOffice functionality through C/C++. Typically this is used by third party components to reuse LibreOffice as a library to convert, view or otherwise interact with documents. LibreOffice internally makes use of "curl" to fetch remote resources such as images hosted on webservers. In affected versions of LibreOffice, when used in LibreOfficeKit mode only, then curl's TLS certification verification was disabled (CURLOPT_SSL_VERIFYPEER of false) In the fixed versions curl operates in LibreOfficeKit mode the same as in standard mode with CURLOPT_SSL_VERIFYPEER of true. This issue affects LibreOffice before version 24.2.4.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Certificate Validation

The product does not validate, or incorrectly validates, a certificate.

How developers prevent this class of flaw

  • Certificates should be carefully managed and checked to assure that data are encrypted with the intended owner's public key.
  • If certificate pinning is being used, ensure that all relevant properties of the certificate are fully validated before the certificate is pinned, including the hostname.

More Improper Certificate Validation vulnerabilities (CWE-295)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in LibreOffice

All LibreOffice vulnerabilities

Recent Improper Certificate Validation vulnerabilities

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