CVE-2026-55045
Local code execution vulnerability in Microsoft Office via out-of-bounds read.
Is CVE-2026-55045 being exploited?
Not confirmed. CVE-2026-55045 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.45% probability of exploitation in the next 30 days.
How severe is CVE-2026-55045?
CVE-2026-55045 is rated High with a CVSS score of 8.4. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-55045?
Yes. A fix has been recorded for CVE-2026-55045. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-55045 affect?
CVE-2026-55045 affects Microsoft Office (desktop). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-55045?
Apply Microsoft security update when released; restrict untrusted files and enable Protected View.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Local code execution when a user opens a crafted Office file, allowing unauthorized execution of arbitrary code under user context.
Patch when possible
- affected>= 16.0.1 and < https://aka.ms/OfficeSecurityReleases
- affected>= 16.0.0 and < 16.0.5561.1000
- affected>= 19.0.0 and < https://aka.ms/OfficeSecurityReleases
- affected>= 1.0.0 and < 16.111.26071215
- affected>= 16.0.1 and < https://aka.ms/OfficeSecurityReleases
- affected>= 16.0.0 and < https://aka.ms/OfficeSecurityReleases
- affected>= 16.0.1 and < 16.111.26071215
- affected>= 16.0.0 and < 16.111.26071215
- affected>= 16.0.0 and < 16.0.5561.1001
- affected>= 16.0.0 and < 16.0.10417.20175
- affected>= 16.0.0 and < 16.0.19725.20434
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.