CVE-2026-8356

CVE-2026-8356 is a medium-severity vulnerability with a CVSS 4.0 base score of 5.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-121.

Key facts

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.

Frequently asked questions

What is CVE-2026-8356?
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.
How severe is CVE-2026-8356?
CVE-2026-8356 has a CVSS 4.0 base score of 5.4, rated medium severity.
Is CVE-2026-8356 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (2nd percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-8356?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-8356 have an EU (EUVD) identifier?
Yes. CVE-2026-8356 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-36738.
When was CVE-2026-8356 published?
CVE-2026-8356 was published on 2026-06-15 and last updated on 2026-06-17.

References

Other CWE-121 (Stack-based Buffer Overflow) vulnerabilities

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