Threats / Microsoft / CVE-2023-28229
CVE-2023-28229
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-08-04
Microsoft Windows CNG Key Isolation Service vulnerability
Microsoft Windows CNG Key Isolation Service contains an unspecified vulnerability allowing attackers to gain limited SYSTEM privileges through improper resource handling.
Verdict
Today item — known-exploited.
A privilege escalation flaw in Windows CNG Key Isolation Service enables local attackers to obtain elevated SYSTEM-level access. Active exploitation in the wild indicates immediate risk to Windows systems requiring prompt patching.
CISA KEV Yes · 2023-10-045EPSS 0.01872 (verify live)6Exploit Public PoC7CVSS 73CISA SSVC Exploitation: active · Automatable: no · Impact: total4
01
Is it exploitable?
— the evidence, ranked above the scoreExploit available
Public proof-of-concept exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported exploitation
1 independent public report of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2023-10-04).
Probability (EPSS)
EPSS 0.01872 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
CVSS 7 (CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C) · Affected: Microsoft, Windows CNG Key Isolation Service. Confirm exact fixed builds in the vendor advisory.CVSS — CNA-assigned (CVE.org), version 3.1, set at disclosure.
Weakness (CWE)
Mapped to CWE-591 CWE-591.CWE — CNA-assigned (CVE.org); the weakness class drives how the flaw is exploited.
CISA SSVC (triage disposition)
Exploitation: active · Automatable: no · Technical Impact: totalCISA's own stakeholder-specific triage inputs, published in the CVE record (CISA Coordinator role). NOTE: this is CISA's three decision points; the final Act/Attend/Track decision also requires a Mission & Well-being input not published here, so no overall decision is asserted.
Currency of the record
CISA added this to its KEV catalog 176 days after the CVE record was published.KEV lag = CISA-KEV dateAdded − CVE.org datePublished; a floor on how long the known-exploited flaw sat in the public record before the federal catalog listed it. Severity/weakness here is CNA- or CISA-assigned (current at disclosure), independent of NVD's analysis backlog.
WeaknessCWE-591 · CWE-591
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution not established
No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.
03
Why it matters
— the attack path, told twice: adversary, then board1
Front door — unauthenticated access narrative 1
Attacker
I execute code with standard user privileges on a target Windows system.
Business
User workstations and servers remain vulnerable to local privilege escalation attacks.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I trigger the vulnerability in the CNG Key Isolation Service to escalate my privileges to SYSTEM level.
Business
Attackers gain unrestricted control over affected systems, enabling lateral movement and persistence.
3
Lateral reach — past segmentation narrative 3
Attacker
I access cryptographic keys and sensitive system resources now available at SYSTEM privilege level.
Business
Confidentiality and integrity of encrypted data and system security controls are compromised.
04
What to do
— defensible action- Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05