CVE-2026-63273 (GCVE-0-2026-63273)

Vulnerability from cvelistv5 – Published: 2026-09-22 11:10 – Updated: 2026-09-28 14:23
VLAI
Title
Heap buffer overflow in PDF import encryption handling
Summary
LibreOffice Draw can import PDF documents. A heap buffer overflow existed when importing an encrypted document. The length of the decryption key was taken from the document's own encryption dictionary and was used to fill a fixed size key buffer without being checked against it, so a length larger than that buffer wrote past its end. In fixed versions a declared key length larger than the buffer is rejected.
Severity
5.4 (Medium)
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N/E:P
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-22 12:27 UTC
CWE
Assigner
Document Fdn. CNA
CNA scorecard C 75/100 over 21 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
The Document Foundation LibreOffice Affected: 26.2 , < < 26.2.5 (26.2 series)
guessed Create a notification for this product.
Date Public
2026-09-21 23:59
Credits
Claude, found by Anthropic using agents to study the security of open-source projects Ada Logics, validating and reporting Anonymous working with TrendAI Zero Day Initiative Caolán McNamara of Collabora Productivity
Show details on NVD website
To clipboard 

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