CVE-2026-63276
Publication date 22 September 2026
Last updated 5 October 2026
Ubuntu priority
Description
LibreOffice converts CFF fonts to Type 1 when it subsets a font, which happens when a document is exported to PDF, and CFF fonts may be embedded in documents. A stack buffer overflow existed in that conversion. The converted operators were written into a fixed size buffer with no check that they still fit, so a glyph emitting many operators wrote past the end of the buffer. In fixed versions the remaining capacity is tracked and the conversion stops when it is used up.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| libreoffice | 26.04 LTS resolute |
Fixed 4:26.2.6.3-0ubuntu0.26.04.2
|
| 24.04 LTS noble |
Fixed 4:24.2.7-0ubuntu0.24.04.7
|
|
| 22.04 LTS jammy |
Fixed 1:7.3.7-0ubuntu0.22.04.13
|
|
| 20.04 LTS focal |
Needs evaluation
|
Severity score breakdown
CVSS version: CVSS v4.0
Base score
5.4 · Medium
Vector: 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
References
Related Ubuntu Security Notices (USN)
- USN-8868-1
- LibreOffice vulnerabilities
- 5 October 2026