Intel

CVE-2026-62870

excel: Use After Free (CVE-2026-62870)

highEPSS 0.8%

Description

Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code over a network.

Source: BSI CSAFBSI WID PortalNVD (NIST)CVE.org (MITRE)cvelistv5Microsoft Security Update Guide

Affected products

The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

microsoft365_apps
microsoftexcel
microsoftoffice_2019
microsoftoffice_2021
microsoftoffice_2024

Metrics

XIEM Effective CVSS
8.8
Source: nvd-v3
EPSS percentile
56.0 %
High — this CVE ranks above the median of all CVEs scored today (rank ≥ 36%).
KEV status
—
Show all metrics
Severity
high
Priority score
93.16
Exploit maturity
no public PoC known
CVSS v3
8.8
EPSS score
0.8 %
Low — model estimates < 1% exploitation likelihood.
Published
2026-08-04 00:17 UTC
CWE
CWE-416

Weakness classes (CWE)

  • CWE-416Variant

    Use After Free

    The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.

    cwe.mitre.org →

References & sources

Reanalysis & status changes

Chronological NVD audit events for this CVE — reanalyses, CVSS updates, CPE diffs.

  1. Initial Analysis2026-08-09 14:32 UTC· nvd@nist.gov
    • CPE Configuration: OR *cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x64:* *cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x86:* *cpe:2.3:a:microsoft:excel:2016:*:*:*:*:*:x64:* *cpe:2.3:a:microsoft:excel:2016:*:*:*:*:*:x86:* *cpe:2.3:a:microsoft:office_2019:-:*:*:*:*:*:x86:* *cpe:2.3:a:microsoft:office_2019:-:*:*:*:*:*:x64:* *cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:-:x64:* *cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:-:x86:* *cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:-:x64:* *cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:-:x86:*
    • Reference Type: Microsoft Corporation: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-62870 Types: Vendor Advisory
  2. New CVE Received2026-08-04 00:17 UTC· secure@microsoft.com
    • Affected: Microsoft 365 Apps for Enterprise, Microsoft Excel 2016, Microsoft Office 2019 (+2)
    • Description: Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code over a network.
    • CVSS V3.1: AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
    • CWE: CWE-416

Linked advisories