Microsoft Windows Privilege Escalation Vulnerability

Known exploitedExploited · KEV 2022-03-15RansomwarePublic exploit codeCVE-2019-0543CWE-287

Exploited since 2022-03-15. No WAF vendor names it yet.

Edge rules

0/8

Our test

No exploit yet

CVSS

7.8

EPSS

4.7% Top 8%

Posts, 14d

Published

2019-01-08

An elevation of privilege vulnerability exists when Windows improperly handles authentication requests, aka "Microsoft Windows Elevation of Privilege Vulnerability." This affects Windows 7, Windows Server 2012 R2, Windows RT 8.1, Windows Server 2008, Windows Server 2019, Windows Server 2012, Windows 8.1, Windows Server 2016, Windows Server 2008 R2, Windows 10, Windows 10 Servers.

Known exploitedLast checked 2026-11-04

The risk

CISA lists CVE-2019-0543 as exploited in the wild since 2022-03-15, including known use in ransomware campaigns. Exploit code is published on Exploit-DB. No edge WAF vendor names it in a changelog, so default managed rules may or may not catch it.

Who is affected

Teams running Microsoft Windows. Affected versions are in the vendor advisory.

Next steps

Find the version you run. In PowerShell (build and latest updates):

Get-ComputerInfo -Property OsName, OsBuildNumber; Get-HotFix | Sort-Object InstalledOn -Descending | Select-Object -First 5

Apply the vendor's fix; the advisory lists the affected and fixed versions.
CISA's required action: Apply updates per vendor instructions. US federal agencies must act by 2022-04-05.
Review exposed instances for signs of compromise: it was exploited before many systems were patched, and a later patch does not undo access already gained.
Do not rely on WAF defaults: no edge vendor names this CVE. Restrict access to the vulnerable component or add a custom rule until it is patched. Edge coverage
Check which WAF sits in front of your site and whether it covers this CVE. Check your domain

Edge coverage

Claimed by vendors

CloudflareBefore feed historyOlder than its feed AWSBefore feed historyOlder than its feed Microsoft AzureNo public claimNot named Google CloudBefore feed historyOlder than its feed FastlyBefore feed historyOlder than its feed F5Before feed historyOlder than its feed AkamaiNo public sourceNo public changelog OWASP CRSBefore feed historyOlder than its feed

Attack traffic on Cloudflare

Cloudflare Radar

Broken Authentication14% of mitigated layer 7 attacks, 7 days
Rules for named CVEs5.9% of mitigated layer 7 attacks, 7 days

Radar groups Cloudflare's WAF managed rules by category; it does not publish counts per CVE. These shares show how much attack traffic targets this kind of flaw across Cloudflare's network (28-day trend). They are not compromised systems, and seeing few attempts on Cloudflare does not prove an absence elsewhere. Radar data as of 2026-11-03. Radar ↗

Check your exposure with an agent

Read-only

Copy this into an agent with access to your infrastructure. It asks for an evidence-based, read-only assessment: affected systems, exposure, compensating controls and what is still unknown. It does not scan or change anything by itself.

Prompt12 lines

Assess whether the infrastructure available to you is affected by CVE-2019-0543 (Microsoft Windows Privilege Escalation Vulnerability). Perform a read-only assessment within your authorized access. Do not send exploit traffic, scan third-party systems, change configuration or restart services.

1. Verify the CVE record at https://www.cve.org/CVERecord?id=CVE-2019-0543 and the vendor advisory. Establish affected and fixed versions, including vendor backports. Cite sources and retrieval dates; flag anything you cannot verify.
2. Inventory deployments of Microsoft Windows: asset, environment, owner where known, installed version or build, and how you confirmed it (package metadata, a version endpoint, image tags), e.g. `Get-ComputerInfo -Property OsName, OsBuildNumber; Get-HotFix | Sort-Object InstalledOn -Descending | Select-Object -First 5` (in PowerShell (build and latest updates)). An image tag alone does not prove the running version.
3. Identify which deployments are reachable from the internet or untrusted networks, and through which paths (direct origin, load balancer, CDN or WAF).
4. Assess compensating controls separately from patch status. Current edge WAF coverage for this CVE: no edge WAF vendor names it. Live data: https://cve.vigilbase.com/api/v1/cves/CVE-2019-0543. Check whether the rule is enabled and in block mode on each path, and whether any path bypasses the WAF. A WAF rule is not a patch.
5. It is known exploited (CISA KEV): review logs on exposed instances for signs of exploitation before and after patching.

Return a short summary and a table: asset | version/build | assessment (affected, fixed, not applicable, unknown) | exposure | compensating control | evidence | next action. List what you could not assess and the access needed to resolve it. Do not infer absence of compromise from patch status or a lack of alerts.

Remediation guidance: Apply the vendor's fix; the advisory lists the affected and fixed versions. CISA's required action: Apply updates per vendor instructions. US federal agencies must act by 2022-04-05.
More: https://cve.vigilbase.com/cve/CVE-2019-0543

Sources

Cited

CVE record

CVSS 3.1 7.8 (high). Weakness: CWE-287.

CVE-2019-0543 ↗NVD ↗

Exploit evidence

Exploit-DB lists 1 exploit.

Exploit-DB: Microsoft Windows 10 - SSPI Network Authentication Session 0 Privilege Escalation ↗

CISA KEV

Added 2022-03-15, federal due date 2022-04-05, known ransomware use (catalog 2026.11.03, checked 2026-11-04).

CISA KEV catalog ↗

EPSS

4.68% probability of exploitation activity in the next 30 days, higher than 91% of CVEs (2026-11-02).

FIRST EPSS ↗

WAF vendor statements

No edge vendor changelog names it.

Ask Vigil

AI · answers from this page

Ask about CVE-2019-0543: who's covered, what to patch first, how vendors compare. I cite sources and won't help with attacks.

Severity, decoded

CVSS 3.1

7.8High

High · 7.8 / 10

Exploitable with local access, with low privileges and no user interaction, leading to full loss of confidentiality, integrity and availability.

Needs local accessAny user loginNo user actionWorks reliablyFull compromise

How the score is built8 metrics

Attack vectorAn attacker needs local access, or must trick a user into opening something on the machine.
Local
Attack complexityNo special conditions are needed; the attack works reliably.
Low
Privileges requiredThe attacker needs an ordinary user account.
Low
User interactionNo one has to click or open anything; the attack works on its own.
None
ScopeThe damage stays within the vulnerable component.
Unchanged
Confidentiality impactAn attacker can read all data the affected component holds, or the most sensitive parts of it.
High
Integrity impactAn attacker can change any data or files the affected component protects.
High
Availability impactAn attacker can take the component down completely or keep it from serving anyone.
High

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CISA's assessmentSSVC, from the CVE record

ExploitationActive

Attackers are exploiting this in the wild.

AutomatableNo

At least one step needs hands-on work, which slows mass attacks.

Technical impactTotal

A successful attack gives full control over the affected software or all of its data.

Public exploits

1 found

0 Metasploit1 Exploit-DB0 Scanner template0 GitHub PoCs

Exploit-DBMicrosoft Windows 10 - SSPI Network Authentication Session 0 Privilege Escalation2019-01-14 · local · windows · verified

Links are to third-party code: never run it outside an isolated lab.

Timeline

2019-01-08
CVE published
CVE List
2019-01-14
Exploit published on Exploit-DB
Microsoft Windows 10 - SSPI Network Authentication Session 0 Privilege Escalation
2022-03-15
Added to CISA KEV
Confirmed exploitation in the wild