CVE-2025-26687: microsoft 365_copilot Use After Free
CVSS: 7.5v3.1HighAnalyzed
Published 08-04-2025Last modified 10-08-2026
Vulnerability summary
CVE-2025-26687 is a high (CVSS 7.5) Use After Free vulnerability in microsoft 365_copilot. EPSS estimates a 1.14% chance of exploitation in the next 30 days, higher than 66.1% of scored vulnerabilities.
CVSS score
7.5/10
010
High · v3.1 (CVE.org)EPSS score
1.14%
0%100%
Low · +0.01 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Timeline
- 08-04-2025PublishedVulnerability first disclosed.
- 10-08-2026Last modifiedVulnerability information updated.
Description
Use after free in Windows Win32K - GRFX allows an unauthorized attacker to elevate privileges over a network.
CVSS metrics
2 scores · 2 sources · 1 versionHigh 7.5Preferred score · CVE.org (CNA)
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:CSourcesAll 2 agree
- NVDNIST7.5HighCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS trend
Probability
1.14%
Chance of exploitation in the next 30 days
Percentile
66%
Versus all other CVEs
30-day change
+0.01 pp
From 1.13% on 19-09-2026
19-09-202619-10-2026
EPSS score1.14%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Microsoft39 products
- 365_copilot< 16.0.18730.20000
- microsoft office for android≥ 16.0.1, < 16.0.18730.20000
- microsoft office for universal≥ 16.0.1, < 16.0.14326.22331
- office< 16.0.14326.22331
- windows_10_1507< 10.0.10240.20978
1 vendor · 39 products
