CVE-2026-68795 is a stack-based buffer overflow in Microsoft Excel's file parsing logic, carrying a CVSS 7.8 (high) rating but an EPSS score of just 0.00332. That gap is the most important thing to understand about this vulnerability — not the raw severity number.
The low EPSS score indicates that Excel's sandbox and defensive layers are currently containing the overflow, which is good news in the short term. However, the structural conditions that produced this bug almost certainly remain. Stack-based buffer overflows persisting in 2026 within one of the most scrutinized applications in existence isn't a failure of individual developer skill — it's a systemic outcome of maintaining a parser that must handle deprecated .xls import logic, BIFF record formats, OLE2 compound document structures, and legacy compatibility shims that nobody has touched in twenty years. These are the "sediment layers" of the codebase: rarely reviewed, actively preserved for backward compatibility, and bridging unsafe C-style memory handling to modern abstractions in ways that introduce subtle overflow conditions.
What should concern defenders most is not this specific CVE but the debt surrounding it. The CVSS/EPSS gap tells you the sandbox held — it tells you nothing about whether functionally equivalent overflow points exist in adjacent code paths within the same parser. Every disclosed-but-unpatched vulnerability in Excel's legacy file format branches compounds the exposure window. When attacker tooling evolves to target this specific entry point, it will likely apply to every application consuming Office file formats through the same automation interfaces.
Actionable steps: First, confirm your deployment environment actually exercises the sandbox — some enterprise configurations run Excel with reduced isolation. Second, audit any automation workflows that consume Excel files programmatically (Power Automate, third-party libraries, COM interop) and treat them as downstream blast radius. Third, flag this CVE as a catalyst to review your organization's vulnerability prioritization: CVSS 7.8 in a well-sandboxed application demands different handling than CVSS 7.8 in a network service, but the presence of the sandbox shouldn't reduce urgency to patch — it should increase scrutiny of whether the same parser logic contains other unpatched flaws that the sandbox might not cover.