CVE-2026-20872
published 2026-01-13CVE-2026-20872: External control of file name or path in Windows NTLM allows an unauthorized attacker to perform spoofing over a network.
PriorityP350medium6.5CVSS 3.1
AVNACLPRNUIRSUCHINAN
EPSS
19.11%
97.0th percentile
External control of file name or path in Windows NTLM allows an unauthorized attacker to perform spoofing over a network.
Affected
45 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| microsoft | windows_10_1607 | < 10.0.14393.8783 | 10.0.14393.8783 |
| microsoft | windows_10_1809 | < 10.0.17763.8276 | 10.0.17763.8276 |
| microsoft | windows_10_21h2 | < 10.0.19044.6809 | 10.0.19044.6809 |
| microsoft | windows_10_22h2 | < 10.0.19045.6809 | 10.0.19045.6809 |
| microsoft | windows_10_version_1607 | >= 10.0.14393.0 < 10.0.14393.8783 | 10.0.14393.8783 |
| microsoft | windows_10_version_1809 | >= 10.0.17763.0 < 10.0.17763.8276 | 10.0.17763.8276 |
| microsoft | windows_10_version_21h2 | >= 10.0.19044.0 < 10.0.19044.6809 | 10.0.19044.6809 |
| microsoft | windows_10_version_22h2 | >= 10.0.19045.0 < 10.0.19045.6809 | 10.0.19045.6809 |
| microsoft | windows_11_23h2 | < 10.0.22631.6491 | 10.0.22631.6491 |
| microsoft | windows_11_24h2 | < 10.0.26100.7623 | 10.0.26100.7623 |
| microsoft | windows_11_25h2 | < 10.0.26200.7623 | 10.0.26200.7623 |
| microsoft | windows_11_version_22h3 | >= 10.0.22631.0 < 10.0.22631.6491 | 10.0.22631.6491 |
| microsoft | windows_11_version_23h2 | >= 10.0.22631.0 < 10.0.22631.6491 | 10.0.22631.6491 |
| microsoft | windows_11_version_24h2 | >= 10.0.26100.0 < 10.0.26100.7623 | 10.0.26100.7623 |
| microsoft | windows_11_version_25h2 | >= 10.0.26200.0 < 10.0.26200.7623 | 10.0.26200.7623 |
| microsoft | windows_server_2008 | — | — |
| microsoft | windows_server_2008_r2_service_pack_1 | >= 6.1.7601.0 < 6.1.7601.28117 | 6.1.7601.28117 |
| microsoft | windows_server_2008_service_pack_2 | >= 6.0.6003.0 < 6.0.6003.23717 | 6.0.6003.23717 |
| microsoft | windows_server_2012 | — | — |
| microsoft | windows_server_2012 | >= 6.2.9200.0 < 6.2.9200.25868 | 6.2.9200.25868 |
| microsoft | windows_server_2012_r2 | >= 6.3.9600.0 < 6.3.9600.22968 | 6.3.9600.22968 |
| microsoft | windows_server_2016 | < 10.0.14393.8783 | 10.0.14393.8783 |
| microsoft | windows_server_2016 | >= 10.0.14393.0 < 10.0.14393.8783 | 10.0.14393.8783 |
| microsoft | windows_server_2019 | < 10.0.17763.8276 | 10.0.17763.8276 |
| microsoft | windows_server_2019 | >= 10.0.17763.0 < 10.0.17763.8276 | 10.0.17763.8276 |
CVSS provenance
nvdv3.16.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
vendor_msrc6.5MEDIUM
Stop checking back — get the weekly exploitation signal.
Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.
Microsoft
NTLM Hash Disclosure Spoofing Vulnerability
vendor_msrc·2026-01-13·CVSS 6.5
CVE-2026-20872 [MEDIUM] CWE-73 NTLM Hash Disclosure Spoofing Vulnerability
NTLM Hash Disclosure Spoofing Vulnerability
Description: External control of file name or path in Windows NTLM allows an unauthorized attacker to perform spoofing over a network.
FAQ: According to the CVSS metric, user interaction is required (UI:R). What interaction would the user have to do?
Minimal interaction with a malicious file by a user such as selecting (single-click), inspecting (right-click), or performing an action other than opening or executing the file could trigger this vulnerability.
Windows NTLM: Windows NTLM
Microsoft: Microsoft
Customer Action Required: Yes
Impact: Spoofing
Exploit Status: Publicly Disclosed:No;Exploited:No;Latest Software Release:Exploitation Less Likely
Reference: https://catalog.update.microsoft.com/v7/site/Search.aspx?q=KB5073723
Reference:
GHSA
GHSA-fpp4-775q-mqrm: External control of file name or path in Windows NTLM allows an unauthorized attacker to perform spoofing over a network
ghsa_unreviewed·2026-01-13
CVE-2026-20872 [MEDIUM] CWE-73 GHSA-fpp4-775q-mqrm: External control of file name or path in Windows NTLM allows an unauthorized attacker to perform spoofing over a network
External control of file name or path in Windows NTLM allows an unauthorized attacker to perform spoofing over a network.
No detection rules found.
No public exploits indexed.
Bleepingcomputer
Microsoft January 2026 Patch Tuesday fixes 3 zero-days, 114 flaws
blogs_bleepingcomputer·2026-01-13·CVSS 5.5
[MEDIUM] Microsoft January 2026 Patch Tuesday fixes 3 zero-days, 114 flaws
## Microsoft January 2026 Patch Tuesday fixes 3 zero-days, 114 flaws
## Lawrence Abrams
57 Elevation of Privilege vulnerabilities
3 Security Feature Bypass vulnerabilities
22 Remote Code Execution vulnerabilities
22 Information Disclosure vulnerabilities
2 Denial of Service vulnerabilities
5 Spoofing vulnerabilities
When BleepingComputer reports on Patch Tuesday security updates, we only count those released by Microsoft today. Therefore, the number of flaws does not include Microsoft Edge (1 flaw) and Mariner vulnerabilities fixed earlier this month.
To learn more about the non-security updates released today, you can review our dedicated articles on the Windows 11 KB5074109 & KB5073455 cumulative updates and Windows 10 KB5073724 extended security update .
## 3 zero-days, one ex
Wiz
CVE-2026-20872 Impact, Exploitability, and Mitigation Steps | Wiz
blogs_wiz·CVSS 6.5
CVE-2026-20872 [MEDIUM] CVE-2026-20872 Impact, Exploitability, and Mitigation Steps | Wiz
## CVE-2026-20872 :
vulnerability analysis and mitigation
External control of file name or path in Windows NTLM allows an unauthorized attacker to perform spoofing over a network.
Source : NVD
## 6.5
Score
Published January 13, 2026
Severity MEDIUM
CNA Score 6.5
Has Public Exploit No
Has CISA KEV Exploit No
CISA KEV Release Date N/A
CISA KEV Due Date N/A
Exploitation Probability Percentile (EPSS) 24.7
Exploitation Probability (EPSS) 0.1
Sources
NVD
## Get a CVE risk assessment
Get a prioritized view of CVEs in your cloud—so you can focus on what's exploitable, not just what's listed.
Free Vulnerability Assessment
## Benchmark your Cloud Security Posture
Evaluate your cloud security practices across 9 security domains to benchmark your risk level and identify gaps
2026-01-13
Published