CVE-2019-1388
CVE-2019-1388 is a security flaw in Microsoft Windows, Microsoft’s operating system for PCs and servers. Someone who already has a foothold can use Microsoft Windows to take full control of the machine. The US Cybersecurity and Infrastructure Security Agency (CISA) added it to its catalog of flaws known to be used in attacks on 7 Apr 2023, and says ransomware gangs have used it.[1]
Microsoft Windows is in things households have, such as phones, computers, browsers and everyday apps, so the fix matters at home as much as at work. Microsoft has published a fix or advice.
Description
CISA calls it a certificate dialog privilege escalation in Microsoft Windows. In its words: “Microsoft Windows Certificate Dialog contains a privilege escalation vulnerability, allowing attackers to run processes in an elevated context.”[1]
The CVE record adds: “An elevation of privilege vulnerability exists in the Windows Certificate Dialog when it does not properly enforce user privileges, aka 'Windows Certificate Dialog Elevation of Privilege Vulnerability'.”[2]
The underlying weakness is improper privilege management (CWE-269), in MITRE’s list of common software weaknesses.
It scores 7.8 out of 10 on the Common Vulnerability Scoring System, which rates it high, scored by NVD using CVSS 3.1.[2]
Affected versions
NVD’s record doesn’t list version ranges for it; Microsoft’s advisory has them[3]. CISA names the product as Microsoft Windows.
Every device with Microsoft Windows needs the update.
Exploitation
CISA added it to its catalog of known exploited vulnerabilities on 7 Apr 2023, 1,242 days after it was made public. CISA lists a flaw only when it has reliable evidence of it being exploited, and gave US federal agencies until 28 Apr 2023 to fix it.[1] CISA says ransomware gangs have used it.
FIRST’s Exploit Prediction Scoring System, which estimates how likely a flaw is to be used in attacks in the next 30 days from what it sees across the internet, puts it at 9%. That’s in the top 5% of the flaws it scores.[4]
CISA assesses it as not automatable: each attack takes some work.
CISA doesn’t say who was attacked, or how.
Fix
Microsoft has published a fix or advice.[3] CISA’s required action: “Apply updates per vendor instructions.”[1]
- Update Microsoft Windows now.On Windows: Settings, Windows Update, Check for updates, then restart. Office updates come the same way, or from any Office app: File, Account, Update Options. Then turn on automatic updates, so the next fix arrives on its own.
- If there’s no update, stop using it.CISA’s advice when a flaw being used in attacks has no fix is to stop using the product until it does.
Timeline
| Date | Event |
|---|---|
| The flaw is made public in the National Vulnerability Database, with a severity score of 7.8.[2] | |
| CISA adds it to its catalog of flaws known to be used in attacks, noting that ransomware gangs have used it.[1] | |
| CISA’s deadline for US government agencies to fix it.[1] | |
| FIRST puts the odds of it being used in attacks in the next 30 days at 9%.[4] |
See also
Other Microsoft Windows flaws
- CVE-2026-96951: command injection ·
- CVE-2026-85880: heap-based buffer overflow ·
- CVE-2026-81963: link following ·
- CVE-2008-4250: buffer overflow ·
- CVE-2026-32202: protection mechanism failure ·
- CVE-2025-60710: link following ·
Other improper privilege management flaws
- CVE-2026-102490, Zammad GmbH Zammad: improper privilege management ·
- CVE-2026-84869, ConnectWise ScreenConnect: improper privilege management and missing authorization ·
- CVE-2026-46817, Oracle E-Business Suite: improper privilege management ·
- CVE-2024-8068, Citrix Session Recording: improper privilege management ·
- CVE-2023-28434, MinIO: security feature bypass ·
Added the same day
- CVE-2023-26083, Arm Mali Graphics Processing Unit (GPU): mali GPU kernel driver information disclosure ·
- CVE-2021-27878, Veritas Backup Exec Agent: command execution ·
- CVE-2021-27877, Veritas Backup Exec Agent: improper authentication ·
- CVE-2021-27876, Veritas Backup Exec Agent: file access ·
Every Microsoft flaw on CISA’s list · Everything added in April 2023
References
- ^ Cybersecurity and Infrastructure Security Agency. “Microsoft Windows Certificate Dialog Privilege Escalation Vulnerability”. Known Exploited Vulnerabilities Catalog, added 7 Apr 2023.
- ^ National Institute of Standards and Technology. “CVE-2019-1388 Detail”. National Vulnerability Database, published 12 Nov 2019.
- ^ Microsoft. Advisories and fixes: portal.msrc.microsoft.com.
- ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.086, percentile 95.1, 31 Oct 2026.
- CVE Program. “CVE-2019-1388”. The official CVE record.
This article is built from CISA’s catalog (version 2026.10.30), NVD’s record and FIRST’s scores, kept in HARD’s database and checked every morning. The plain English is HARD’s.