CVE-2025-21418: Microsoft Windows 10 Version 1507 · Heap-based Buffer Overflow
Affects Microsoft Windows 10 Version 1507Source CVE Database V5
Exploited in the wild · KEV due 4 Mar 2025 · 2% EPSS : apply the vendor's fix or mitigations to Microsoft Windows 10 Version 1507 now.
Data as of 26 Oct 2026, 07:57 UTC
- KEV deadline
- US federal agencies must patch by this date; a sensible deadline for everyone else.
- EPSS
- 2.1% chance of exploitation in 30 days – higher than 81% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:CExploitation evidence
t = 0 is the CVE’s publication on cve.org
Disclosed: evidence found.
CVE published 11 Feb 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: evidence found.
Listed in CISA KEV the same day as disclosure
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
Timeline
CVE ID reserved
by microsoft
, 62 days before disclosure
CVE published
on cve.org
, t = 0
Added to CISA KEV (opens in a new tab)
exploitation confirmed
, the same day as disclosure
KEV remediation due
US federal deadline
, 21 days after disclosure
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CISA KEV (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.
What to do
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Microsoft Windows 10 Version 1507 | Affected
| Fixed in– |
Description
Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability