Evidence used
- No CISA KEV confirmation is currently recorded.
- Exploitation requires an existing local or physical foothold with privileges.
- EPSS is 1.32% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2020
CVE-2019-9510High confidence
Microsoft Windows RDP can bypass the Windows lock screen
Microsoft · Windows 10 or newer system using RDP
5.3MediumCVSS 3.1
Scheduled
Patch availableMedium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityMedium→Operational priority:Low, lowered one band.downgradedsince 17 Sep 2024
Compensating controls
- Validate the affected product branch and deploy the verified fixed release.
- Restrict local access and enforce least privilege on affected hosts.
- Monitor vendor guidance and exploitation sources for a material change.
Verification
- Confirm that the asset runs Microsoft Windows 10 or newer system using RDP and falls inside the recorded affected range.
- Verify the installed build against the product-specific fixed version after deployment.
- Validate exposure, authentication requirements and compensating controls in the actual environment.
- Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.
Patch available01
What, why and how
A vulnerability in Microsoft Windows 10 1803 and Windows Server 2019 and later systems can allow authenticated RDP-connected clients to gain access to user sessions without needing to interact with the Windows lock screen. Should a network anomaly trigger a temporary RDP disconnect, Automatic Reconnection of the RDP session will be restored to an unlocked state, regardless of how the remote system was left. By interrupting network connectivity of a system, an attacker with access to a system being used as a Windows RDP client can gain access to a connected remote system, regardless of whether or not the remote system was locked. This issue affects Microsoft Windows 10, version 1803 and later, and Microsoft Windows Server 2019, version 2019 and later.
What
A vulnerability in Microsoft Windows 10 1803 and Windows Server 2019 and later systems can allow authenticated RDP-connected clients to gain access to user sessions without needing to interact with the Windows lock screen. Should a network anomaly trigger a temporary RDP disconnect, Automatic Reconnection of the RDP session will be restored to an unlocked state, regardless of how the remote system was left. By interrupting network connectivity of a system, an attacker with access to a system being used as a Windows RDP client can gain access to a connected remote system, regardless of whether or not the remote system was locked. This issue affects Microsoft Windows 10, version 1803 and later, and Microsoft Windows Server 2019, version 2019 and later.
Why
The product requires authentication, but the product has an alternate path or channel that does not require authentication.
How
An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
What
A vulnerability in Microsoft Windows 10 1803 and Windows Server 2019 and later systems can allow authenticated RDP-connected clients to gain access to user sessions without needing to interact with the Windows lock screen. Should a network anomaly trigger a temporary RDP disconnect, Automatic Reconnection of the RDP session will be restored to an unlocked state, regardless of how the remote system was left. By interrupting network connectivity of a system, an attacker with access to a system being used as a Windows RDP client can gain access to a connected remote system, regardless of whether or not the remote system was locked. This issue affects Microsoft Windows 10, version 1803 and later, and Microsoft Windows Server 2019, version 2019 and later.
Why
The product requires authentication, but the product has an alternate path or channel that does not require authentication.
How
An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
02
Exploit reality and attack path
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
Observed exploitation No confirmed evidence
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
Public PoC / exploit material None recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
- Likely attack path
- local access → Authentication Bypass Using an Alternate Path or Channel → cause the confidentiality, integrity or availability impact described by the vendor
- Attack surface
- Local
- Privileges required
- Low: a basic authenticated account is required
- User interaction
- None
- Attack complexity
- Low: no specialised conditions are recorded
- Security boundary
- Unchanged: impact remains within the vulnerable component's security authority
- Weakness
?
CWE means Common Weakness Enumeration: a standard category for the underlying weakness. - CWE-288 ↗
CWE-288: Authentication Bypass Using an Alternate Path or Channel. The product requires authentication, but the product has an alternate path or channel that does not require authentication.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:LCommon Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVLocalAttack vector: The attacker needs local access to the vulnerable system.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CLowConfidentiality impact: A successful attack can cause a limited loss.ILowIntegrity impact: A successful attack can cause a limited loss.ALowAvailability impact: A successful attack can cause a limited loss.- Post-exploitation / living off the land
- The issue can support a local privilege or sandbox boundary transition; normal system utilities may then be available in the gained context.
03
Patch and workaround
Operational remediation based on structured source evidence.
- Status
?
Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change. - Patch available
- Action
- Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
- Workaround
- No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04
Evidence and provenance
Published 15 Jan 2020 · Last source change 17 Sept 2024, 04:00 UTC · CWE-288 · Authentication Bypass Using an Alternate Path or Channel
CVE recordCVE.org · 5.1
CVSS sourceCNA
EPSS source FIRST · tracked since 2026-08-14
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2019-18884
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD modified after enrichment
Core structured fields are present and their contributing authorities are shown above.
Material change intelligence
View recent updates ↗What changed after publication
No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.
CVE published
Fixed release or patch reference recorded
Technical terms and abbreviations used in this report
- CVE
- Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
- CVSS
- Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
- EPSS
- Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
- CWE
- Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
- CNA
- CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
- CISA ADP
- Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
- NVD
- National Vulnerability Database: NIST's enrichment service for CVE records.
- CERT / CSIRT
- A computer security incident response team that publishes warnings or coordinates incident response.
- PoC
- Proof of concept: public material that demonstrates or helps reproduce exploitation.
- CSAF
- Common Security Advisory Framework: a machine-readable format for security advisories.
- LoTL
- Living off the land: abuse of legitimate tools or system functions during an attack.