CVE-2019-0803

An elevation of privilege vulnerability exists in Windows when the Win32k component fails to properly handle objects in memory, aka 'Win32k Elevation of Privilege Vulnerability'. This CVE ID is unique from CVE-2019-0685, CVE-2019-0859.

CVSS: 7.8Highscored by CISA
Exploited in the wild: Yes, in CISA KEV since 3 Nov 2021CISA deadline for US federal agencies: 3 May 2022known use in ransomware campaignspublic exploit code
EPSS: 45.2%chance of exploitation in the next 30 daystop 2% of scored CVEsFIRST score of 11 Nov 2026
Fix: Patch availablesee the advisories in the references
Published: 9 Apr 2019analysed here 12 Nov 2026

Do first. Apply updates per vendor instructions. (CISA's required action for this KEV entry)

Summary

Triage

Exploitable: At runtime
Attack vector: local
Can a WAF block it?: No. See why

The summary, impact and action text on this page are written by our AI analysis pipeline, or taken from the NVD description when a CVE was imported from NVD. They are not the vendor's wording: check them against the sources. A longer AI executive summary and technical analysis are generated for signed-in accounts on the Max plan.

Affected products

Product	Affected versions	Vendor says fixed in
Microsoft Windows	7 for 32-bit Systems Service Pack 17 for x64-based Systems Service Pack 18.1 for 32-bit systems8.1 for x64-based systemsRT 8.110 for 32-bit Systems10 for x64-based Systems10 Version 1607 for 32-bit Systems10 Version 1607 for x64-based Systems10 Version 1703 for 32-bit Systems10 Version 1703 for x64-based Systems10 Version 1709 for 32-bit Systems10 Version 1709 for x64-based Systems10 Version 1803 for 32-bit Systems10 Version 1803 for x64-based Systems10 Version 1803 for ARM64-based Systems10 Version 1809 for 32-bit Systems10 Version 1809 for x64-based Systems10 Version 1809 for ARM64-based Systems10 Version 1709 for ARM64-based SystemsVendor says fixed in: not stated	Not stated by the vendor
Microsoft Windows Server	2008 R2 for x64-based Systems Service Pack 1 (Core installation)2008 R2 for Itanium-Based Systems Service Pack 12008 R2 for x64-based Systems Service Pack 12008 for 32-bit Systems Service Pack 2 (Core installation)20122012 (Core installation)2012 R22012 R2 (Core installation)20162016 (Core installation)version 1709 (Core Installation)version 1803 (Core Installation)20192019 (Core installation)2008 for Itanium-Based Systems Service Pack 22008 for 32-bit Systems Service Pack 22008 for x64-based Systems Service Pack 22008 for x64-based Systems Service Pack 2 (Core installation)Vendor says fixed in: not stated	Not stated by the vendor

As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.

Products named in our analysis

microsoft:windows_10_1507
microsoft:windows_10_1607
microsoft:windows_10_1703
microsoft:windows_10_1709
microsoft:windows_10_1803
microsoft:windows_10_1809
microsoft:windows_7
microsoft:windows_8.1
microsoft:windows_rt_8.1
microsoft:windows_server_1709
microsoft:windows_server_1803
microsoft:windows_server_2008
microsoft:windows_server_2012
microsoft:windows_server_2016
microsoft:windows_server_2019

Fix and mitigation

WAF and other mitigations

Can a WAF block it? No. The attack needs local access to the machine, so a WAF is not on its path.

Also consider: patch

Based on the attack vector (local or physical access). We check Cloudflare, AWS, Google Cloud Armor and Azure; for Akamai, Imperva, Fastly, F5, ask your vendor.

Remediation steps (AI-written)

Step-by-step remediation is generated for accounts on the Max plan, for CVEs that match a technology in their stack. Add this technology to your stack to see the fix checklist.

Exploitation evidence

CISA KEV catalog: Listed since 3 Nov 2021. Known use in ransomware campaigns.
CISA due date: 3 May 2022, the remediation deadline for US federal agencies
CISA required action: Apply updates per vendor instructions.
Public exploit code: Yes: 1 on Exploit-DB · 2 GitHub proofs of concept
CISA SSVC: exploitation active, automatable no, technical impact totalAssessed by CISA 7 Feb 2025 (SSVC 2.0.3). Exploitation is none, poc (public proof of concept) or active.

Exploit-DB

Microsoft Windows - 'Win32k' Local Privilege Escalationlocal, 15 May 2019

GitHub proofs of concept

ExpLife0011/CVE-2019-080382 stars
Iamgublin/CVE-2019-08031 stars

Listed so you can judge urgency, not as a recommendation to run anything. GitHub “proofs of concept” are unvetted: some are fake or carry malware. Exploit-DB marks the entries its staff verified.

Timeline

9 Apr 2019Published
15 May 2019First public exploit or proof of concept35 days later
3 Nov 2021Added to CISA KEV (exploited in the wild)903 days (about 2 years) later
3 May 2022CISA remediation due date (US federal agencies)181 days (about 6 months) later
7 Feb 2025CISA SSVC assessment: exploitation active1,012 days (about 3 years) later
21 Oct 2025CVE record last updated256 days (about 9 months) later
12 Nov 2026Analysed by vulneraibility.com387 days (about 1 year) later

CVSS vector

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

Metric	Value	What it means
Attack vector	LocalLocal access required (shell, logged-in user).	Local access required (shell, logged-in user).
Attack complexity	LowRepeatable attack, no special conditions.	Repeatable attack, no special conditions.
Privileges required	LowThe attacker needs basic user privileges.	The attacker needs basic user privileges.
User interaction	NoneNo victim action needed.	No victim action needed.
Scope	UnchangedImpact stays within the vulnerable component.	Impact stays within the vulnerable component.
Confidentiality	HighTotal data disclosure possible.	Total data disclosure possible.
Integrity	HighComplete modification possible.	Complete modification possible.
Availability	HighFull outage possible.	Full outage possible.

Common questions

Is CVE-2019-0803 being exploited?

Yes. CVE-2019-0803 appears in CISA's Known Exploited Vulnerabilities catalog, which means exploitation in the wild has been confirmed and reported. Treat it as active rather than theoretical, and patch it ahead of higher-scoring vulnerabilities that carry no exploitation evidence.

How severe is CVE-2019-0803?

CVE-2019-0803 is rated High with a CVSS score of 7.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.

Is there a patch for CVE-2019-0803?

Yes. A fix has been recorded for CVE-2019-0803. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.

What does CVE-2019-0803 affect?

CVE-2019-0803 affects microsoft:windows_10_1507, microsoft:windows_10_1607, microsoft:windows_10_1703, microsoft:windows_10_1709, and 11 further products or versions. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.

Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.

References

NVD CVE.org CVE Details Source

3 references in the CVE record, grouped by the tags the record gives them.

Where the data on this page comes from

CVE List (CVE.org): description, affected versions, references; CVE Terms of Use
NVD: CVSS and CPE data
CISA KEV catalog: exploitation, date added, due date
CISA Vulnrichment (ADP): SSVC decision points
FIRST EPSS: exploit probability and percentile
Exploit-DB: published exploits
PoC-in-GitHub: GitHub repositories that claim a proof of concept

Summary, impact and triage tags: written by our AI analysis pipeline from the sources above. Check them against the sources.

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