Medium severity · published Sep 22, 2026
CVE-2026-63274
Heap buffer overflow in PDF import stream handling
5.4
CVSS
0.2%
EPSS
No
On KEV
Description
LibreOffice Draw can import PDF documents. A heap buffer overflow existed when importing a stream object. The length of the stream was taken from the object's own dictionary and was not checked against the number of bytes actually present, so copying the stream read and wrote past the end of the buffer holding it. In fixed versions the declared length is clamped to the bytes actually read.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 9% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
LibreOffice · The Document Foundation
26.2 before < 26.2.5 · source: vendor
In the news
VulnerabilityHigh
ZDI-26-782: LibreOffice PDF File Parsing Heap-based Buffer Overflow Remote Code Execution Vulnerability
This vulnerability allows remote attackers to execute arbitrary code on affected installations of LibreOffice. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The ZDI has assigned a CVSS rating of 7.8. The following CVEs are assigned: CVE-2026-63274.
Oct 16, 2026·Zero Day Initiative
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-63274
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-63274
www.libreoffice.org
https://www.libreoffice.org/about-us/security/advisories/cve-2026-63274
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