Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2025-27473 is a high-severity Uncontrolled Resource Consumption (CWE-400) vulnerability in Microsoft Windows Server 2008. Its CVSS base score is 7.5 (High).
Operationally, ranked in the top 17% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to SC-5 (Denial-of-service Protection) and SC-6 (Resource Availability) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2025-27473 is an uncontrolled resource consumption vulnerability, tracked under CWE-400, that affects the HTTP.sys kernel-mode driver in Windows. The flaw permits remote attackers to trigger excessive resource use through specially crafted network traffic, resulting in denial of service without any authentication or user interaction required.
An unauthenticated attacker with network access can exploit the issue over the internet or internal networks to exhaust resources in HTTP.sys, rendering affected systems unresponsive. The vulnerability carries a CVSS v3.1 score of 7.5, reflecting its high availability impact combined with low attack complexity and no prerequisites.
Microsoft's advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-27473 addresses the flaw and is the authoritative source for mitigation steps, including available patches.
The EPSS score for this CVE reached a peak of 0.4442 after disclosure before settling at a current value of 0.2927, indicating a material rise in exploitation interest that warrants renewed attention from defenders.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2025-10170
Vulnerability Data
Uncontrolled resource consumption in Windows HTTP.sys allows an unauthorized attacker to deny service over a network.
- CWE(s)
Related Threats
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
SC-5 directly limits the effects of resource-exhaustion events that constitute uncontrolled consumption.
SC-6 enforces explicit allocation limits on resources, structurally preventing the weakness from occurring.
Process isolation confines resource consumption to separate domains, reducing blast radius without stopping the root flaw.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Resource-utilization monitoring and alerting on bottlenecks or overloads limits the impact of denial-of-service or resource-exhaustion attacks.
A.8.6's monitoring, stress-testing, projections, tuning, demand-reduction steps (e.g. optimizing queries, deleting obsolete data, restricting non-critical bandwidth) and capacity planning directly stop most uncontrolled consumption from being exploitable by keeping resources within safe bounds; the bounded remainder is algorithmic flaws (e.g. infinite loops, uncontrolled recursion) that no amount of capacity planning can prevent from exhausting a resource when triggered.
Early notification of anomalous resource consumption or system malfunctions enables throttling or isolation before availability is lost.
Monitoring network service usage and applying controls to restrict access when necessary limits an attacker’s ability to consume excessive resources through unrestricted or unauthenticated service calls.
Hardening callouts derived
DISA STIG baselines are authored against specific weaknesses. Where this CVE cites a broad weakness class, the mapping is not asserted at that abstraction (owner ruling, 2026-09-25: grade only at Base and below), so no rule is shown here rather than a rule shown against the wrong grain.
- No fine-grained STIG row for CWE-400, a class-level weakness. Rules are authored against its narrower children: CWE-770.