Evidence used
- No CISA KEV confirmation is currently recorded.
- EPSS is 0.97% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2019
CVE-2019-5531High confidence
VMware VMware vSphere ESXi: Insufficient Session Expiration
VMware · VMware vSphere ESXi
5.4MediumCVSS 3.1
Scheduled
Mitigation 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:Medium, unchanged from published severity.unchanged
Compensating controls
- Apply the linked authoritative mitigation while planning the permanent fix.
- Restrict the affected network interface to trusted sources where business-safe.
- Monitor vendor guidance and exploitation sources for a material change.
Verification
- Confirm that the asset runs VMware VMware vSphere ESXi and falls inside the recorded affected range.
- Recheck the vendor advisory before scheduling a change because no verified fixed version is currently retained.
- 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.
Mitigation available01
What, why and how
VMware vSphere ESXi (6.7 prior to ESXi670-201810101-SG, 6.5 prior to ESXi650-201811102-SG, and 6.0 prior to ESXi600-201807103-SG) and VMware vCenter Server (6.7 prior to 6.7 U1b, 6.5 prior to 6.5 U2b, and 6.0 prior to 6.0 U3j) contain an information disclosure vulnerability in clients arising from insufficient session expiration. An attacker with physical access or an ability to mimic a websocket connection to a user’s browser may be able to obtain control of a VM Console after the user has logged out or their session has timed out.
What
VMware vSphere ESXi (6.7 prior to ESXi670-201810101-SG, 6.5 prior to ESXi650-201811102-SG, and 6.0 prior to ESXi600-201807103-SG) and VMware vCenter Server (6.7 prior to 6.7 U1b, 6.5 prior to 6.5 U2b, and 6.0 prior to 6.0 U3j) contain an information disclosure vulnerability in clients arising from insufficient session expiration. An attacker with physical access or an ability to mimic a websocket connection to a user’s browser may be able to obtain control of a VM Console after the user has logged out or their session has timed out.
Why
According to WASC, Insufficient Session Expiration is when a web site permits an attacker to reuse old session credentials or session IDs for authorization.
How
An attacker operating through a network path may attempt exploitation without authentication after a user interaction. If successful, the issue may obtain information outside the intended access boundary.
What
VMware vSphere ESXi (6.7 prior to ESXi670-201810101-SG, 6.5 prior to ESXi650-201811102-SG, and 6.0 prior to ESXi600-201807103-SG) and VMware vCenter Server (6.7 prior to 6.7 U1b, 6.5 prior to 6.5 U2b, and 6.0 prior to 6.0 U3j) contain an information disclosure vulnerability in clients arising from insufficient session expiration. An attacker with physical access or an ability to mimic a websocket connection to a user’s browser may be able to obtain control of a VM Console after the user has logged out or their session has timed out.
Why
According to WASC, Insufficient Session Expiration is when a web site permits an attacker to reuse old session credentials or session IDs for authorization.
How
An attacker operating through a network path may attempt exploitation without authentication after a user interaction. If successful, the issue may obtain information outside the intended access boundary.
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
- a network path → Insufficient Session Expiration → obtain information outside the intended access boundary
- Attack surface
- Network
- Privileges required
- None: unauthenticated exploitation is possible
- User interaction
- Required interaction required
- 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-613 ↗
CWE-613: Insufficient Session Expiration. According to WASC, Insufficient Session Expiration is when a web site permits an attacker to reuse old session credentials or session IDs for authorization.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:NCommon Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UIRequiredUser interaction: Another user must perform an action for exploitation to succeed.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.ANoneAvailability impact: No direct loss is represented by this metric.- Post-exploitation / living off the land
- No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
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. - Mitigation available
- Affected
- Action
- The Cyber Centre encourages users to review the VMware Security Advisories webpage and apply the necessary updates:
- Workaround
- No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04
Evidence and provenance
Published 18 Sept 2019 · Last source change 4 Aug 2024, 20:01 UTC · CWE-613 · Insufficient Session Expiration
CVE recordCVE.org · 5.1
CVSS sourceNIST NVD
EPSS source FIRST · tracked since 2026-09-01
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2019-15106
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceNIST NVD
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
- ENISA EUVD mappingEUVD-2019-15106 was added to the official ENISA EUVD mapping for this CVE.ENISA EUVD ↗
- Before
- not recorded
- After
- {"euvdId":"EUVD-2019-15106"}
- SeveritySeverity changed from Unknown to Medium.NIST NVD ↗
- Before
- Unknown
- After
- Medium
- CVSS scoreCVSS score changed from not recorded to 5.4 (CVSS 3.1 · NIST NVD · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N).NIST NVD ↗
- Before
- not recorded
- After
- 5.4 (CVSS 3.1 · NIST NVD · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N)
- Catalogue recordCVE added to the BlackTree catalogue.CNA ↗
- Remediation statusRemediation status changed from Awaiting fix to Mitigation available.Canadian Centre for Cyber Security ↗
- Before
- Awaiting fix
- After
- Mitigation available
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.