Cyber Resilience

CVE-2025-33073

HighCISA KEVActive ExploitationEUVD Exploited

Published: 10 June 2025

Published
10 June 2025
Modified
27 October 2025
KEV Added
20 October 2025
Patch
CVSS Score v3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.4433 97.6th percentile
Risk Priority 64 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-33073 is a high-severity Improper Access Control (CWE-284) vulnerability in Microsoft Windows Server 2008. Its CVSS base score is 8.8 (High).

Operationally, ranked in the top 2.4% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.

The strongest mitigations our analysis identified are NIST 800-53 AC-3 (Access Enforcement) and AC-17 (Remote Access).

Deeper analysis

CVE-2025-33073 is an improper access control vulnerability in Windows SMB that permits privilege escalation over a network. The flaw is tracked under CWE-284 and carries a CVSS 3.1 score of 8.8, reflecting network attack vector, low complexity, and low required privileges. It affects Microsoft Windows SMB components across supported Microsoft products.

An authorized attacker with valid credentials can exploit the weakness remotely to obtain higher privileges on the target system, potentially leading to full control over affected hosts.

Microsoft's advisory at msrc.microsoft.com details the issue and available updates, while Vicarius has published detection and mitigation scripts for environments where immediate patching is delayed. The vulnerability is also listed in CISA's Known Exploited Vulnerabilities catalog, indicating confirmed in-the-wild use.

EPSS for the CVE rose from lower values after disclosure to a peak of 0.5758 on 2026-03-14 before receding to the current 0.4433, signaling sustained exploitation interest that warrants ongoing monitoring.

EU & UK References

Vulnerability details

Improper access control in Windows SMB allows an authorized attacker to elevate privileges over a network.

CWE(s)
KEV Date Added
20 October 2025

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

microsoft
windows 10 1507
≤ 10.0.10240.21034 · ≤ 10.0.10240.21034
microsoft
windows 10 1607
≤ 10.0.14393.8148 · ≤ 10.0.14393.8148
microsoft
windows 10 1809
≤ 10.0.17763.7434 · ≤ 10.0.17763.7434
microsoft
windows 10 21h2
≤ 10.0.19044.5965
microsoft
windows 10 22h2
≤ 10.0.19045.5965
microsoft
windows 11 22h2
≤ 10.0.22621.5472
microsoft
windows 11 23h2
≤ 10.0.22631.5472
microsoft
windows 11 24h2
≤ 10.0.26100.4270
microsoft
windows server 2008
all versions, r2
microsoft
windows server 2012
all versions, r2
+5 more product configuration(s) — see NVD for full list

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly enforces access control policies on SMB shares and sessions to block unauthorized privilege elevation by authorized users.

prevent

Limits privileges granted to SMB-authenticated accounts so that an authorized low-privilege attacker cannot escalate rights.

AC-17 Remote Access partial match
prevent

Requires explicit authorization and security controls for all network-based SMB remote access, reducing the attack surface for this network vector.

References