CVE-2023-23409
Microsoft Windows Server 2008 r2
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:NCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2023-23409 is a medium-severity Improper Input Validation (CWE-20) vulnerability in Microsoft Windows Server 2008. Its CVSS base score is 5.5 (Medium).
Operationally, ranked at the 39th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
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-2023-23409 is an information disclosure vulnerability in the Client Server Run-Time Subsystem (CSRSS) component of Windows. It carries a CVSS 3.1 base score of 5.5 and is associated with CWE-20 and CWE-668. The flaw was published on 14 March 2023.
An attacker with local access and low privileges can exploit the issue without user interaction to read sensitive information from memory. The vulnerability permits high confidentiality impact while leaving integrity and availability unaffected.
Microsoft published an advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-23409 that addresses the flaw. The associated EPSS score has remained flat at a peak of 0.0631 with no material increase after disclosure.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-27509
Vulnerability Data
Client Server Run-Time Subsystem (CSRSS) Information Disclosure Vulnerability
- CWE(s)
Related Threats
CVEs Like This One
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Controls whether organization resources are exposed to external system spheres by permitting or prohibiting their use.
The control ensures information is not released into a security sphere where the recipient lacks matching access authorizations.
The control ensures information resources are not exposed to the incorrect (public) sphere through review and authorization.
Protects against data mining that would expose resources to unauthorized spheres by enforcing detection and controls.
Restricts information flows to ensure resources are not exposed to incorrect or unauthorized spheres.
Controlling internal connections prevents exposure of resources to unintended internal spheres.
Knowing exact processing and storage locations helps avoid exposure of resources to incorrect spheres.
The control prevents exposure of the media resource to the wrong security sphere.
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.
A.8.25 mandates security requirements, secure coding guidelines, checkpoints, testing (incl. code scans) and developer training in the SDLC, which reaches a slice of input validation defects but leaves the majority (incomplete enforcement, second-order inputs, parser differentials, post-validation canonicalization) unaddressed as in the SA-3 and A.8.28 anchors.
Mandating input controls that include integrity checks and input validation ensures that untrusted data is examined before use, blocking the root cause of many injection and malformed-data weaknesses.
Security-by-design principles explicitly call for data validation and sanitization at every layer, reducing the chance that malformed or malicious input will be processed without scrutiny.
Requiring language-specific secure coding standards, peer review, SAST and documented mitigation of common programming errors forces validation of all inputs before they are trusted.
Testing against a defined set of requirements and using code review plus vulnerability scanning forces validation of inputs and handling of unanticipated conditions, reducing the chance that malformed data will be accepted.
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.