CVE-2019-9853: LibreOffice documents can contain macros. The execution of those macros is controlled by the document security settings, typically execution of macros...

Description

LibreOffice documents can contain macros. The execution of those macros is controlled by the document security settings, typically execution of macros are blocked by default. A URL decoding flaw existed in how the urls to the macros within the document were processed and categorized, resulting in the possibility to construct a document where macro execution bypassed the security settings. The documents were correctly detected as containing macros, and prompted the user to their existence within the documents, but macros within the document were subsequently not controlled by the security settings allowing arbitrary macro execution This issue affects: LibreOffice 6.2 series versions prior to 6.2.7; LibreOffice 6.3 series versions prior to 6.3.1.

Metrics

CVSS 3.1

7.8/10

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

EPSS Probability

3.21%

86.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Libreoffice	Libreoffice	>= 6.2.0, < 6.2.6
Libreoffice	Libreoffice	>= 6.3.0, < 6.3.1

References

Timeline

Published: Sep 27, 2019
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2019-9853?

LibreOffice documents can contain macros. The execution of those macros is controlled by the document security settings, typically execution of macros are blocked by default. A URL decoding flaw existed in how the urls to the macros within the document were processed and categorized, resulting in the possibility to construct a document where macro execution bypassed the security settings. The documents were correctly detected as containing macros, and prompted the user to their existence within the documents, but macros within the document were subsequently not controlled by the security settings allowing arbitrary macro execution This issue affects: LibreOffice 6.2 series versions prior to 6.2.7; LibreOffice 6.3 series versions prior to 6.3.1.

How severe is CVE-2019-9853?

CVE-2019-9853 has a CVSS score of 7.8/10 (HIGH severity). The EPSS model estimates a 3.21% probability of exploitation in the next 30 days.

How do I fix CVE-2019-9853?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.