Vulnerability · Published Jun 15, 2026 · Assigned by Document Fdn.
CVE-2026-8356Stack buffer overflow in PPT presentation import
Medium 5.4
In plain English
A medium-severity out-of-bounds write in LibreOffice from The Document Foundation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 5% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
LibreOffice can import presentations in the legacy binary PPT format. A stack buffer overflow existed when importing a colour-replacement record. Two fixed-size colour tables were filled from the file, but the write position was not reset between the two passes over the record, so a file whose combined colour counts exceeded the table size wrote past the end of the tables on the stack. In fixed versions the unused second pass is no longer read into those tables.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | libreoffice | 4:7.4.7-1+deb12u13 | DEBIAN-CVE-2026-8356 |
| Debian:13 | libreoffice | 4:25.2.3-2+deb13u5 | DEBIAN-CVE-2026-8356 |
| Debian:14 | libreoffice | 4:26.2.4.2-1 | DEBIAN-CVE-2026-8356 |
| Ubuntu:22.04:LTS | libreoffice | 1:7.3.7-0ubuntu0.22.04.12 | UBUNTU-CVE-2026-8356 |
| Ubuntu:22.04:LTS | libreoffice | 1:7.3.7-0ubuntu0.22.04.12 | USN-8534-1 |
| Ubuntu:24.04:LTS | libreoffice | 4:24.2.7-0ubuntu0.24.04.6 | USN-8534-1 |
| Ubuntu:24.04:LTS | libreoffice | 4:24.2.7-0ubuntu0.24.04.6 | UBUNTU-CVE-2026-8356 |
| Ubuntu:25.10 | libreoffice | no fix listed | UBUNTU-CVE-2026-8356 |
| Ubuntu:26.04:LTS | libreoffice | 4:26.2.4.2-0ubuntu0.26.04.2 | USN-8534-1 |
| Ubuntu:26.04:LTS | libreoffice | 4:26.2.4.2-0ubuntu0.26.04.2 | UBUNTU-CVE-2026-8356 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| The Document Foundation | LibreOffice | 26.2 – before < 26.2.4 |
Weakness: CWE-787, CWE-121 · 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