CVE-2026-77991 - Vulnerability Details - OpenCVE

Joomla Extension - joomlaeventmanager.net - Privileged remote code execution in Joomla Event Manager < 5.0.1 - The administrator source model allows to write dangerous file type incl. PHP, leading to remote code execution.

Attack Vector Network

Attack Complexity Low

Privileges Required High

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact High

Vulnerable System Integrity Impact High

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact High

Subsequent System Integrity Impact High

Subsequent System Availability Impact High

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

No data.

No data.

No data.

No data.

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://www.joomlaeventmanager.net/

History

Thu, 27 Aug 2026 06:15:00 +0000

Type	Values Removed	Values Added
Description		Joomla Extension - joomlaeventmanager.net - Privileged remote code execution in Joomla Event Manager < 5.0.1 - The administrator source model allows to write dangerous file type incl. PHP, leading to remote code execution.
Title		Joomla Extension - joomlaeventmanager.net - Privileged remote code execution in Joomla Event Manager < 5.0.1
Weaknesses		CWE-434
References		https://www.joomlaeventmanager.net/
Metrics		cvssV4_0 `{'score': 9.4, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H'}`

Projects

Sign in to view the affected projects.

MITRE

Status: PUBLISHED

Assigner: Joomla

Published: 2026-08-27T05:50:13.521Z

Updated: 2026-08-27T05:50:13.521Z

Reserved: 2026-08-21T19:05:09.013Z

Link: CVE-2026-77991

Vulnrichment

No data.

NVD

Status : Received

Published: 2026-08-27T06:17:28.970

Modified: 2026-08-27T06:17:28.970

Link: CVE-2026-77991

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-434

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-77991", "assignerOrgId": "6ff30186-7fb7-4ad9-be33-533e7b05e586", "state": "PUBLISHED", "assignerShortName": "Joomla", "dateReserved": "2026-08-21T19:05:09.013Z", "datePublished": "2026-08-27T05:50:13.521Z", "dateUpdated": "2026-08-27T05:50:13.521Z"}, "containers": {"cna": {"affected": [{"defaultStatus": "unaffected", "product": "JEM - Joomla Event Manager extension for Joomla", "vendor": "joomlaeventmanager.net", "versions": [{"status": "affected", "version": "1.0.0-5.0.0"}]}], "credits": [{"lang": "en", "type": "finder", "value": "Phil Taylor, mysites.guru"}], "descriptions": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "Joomla Extension - joomlaeventmanager.net - Privileged remote code execution in Joomla Event Manager < 5.0.1 - The administrator source model allows to write dangerous file type incl. PHP, leading to remote code execution."}], "value": "Joomla Extension - joomlaeventmanager.net - Privileged remote code execution in Joomla Event Manager < 5.0.1 - The administrator source model allows to write dangerous file type incl. PHP, leading to remote code execution."}], "metrics": [{"cvssV4_0": {"attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "HIGH", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "subConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "subIntegrityImpact": "HIGH", "vulnAvailabilityImpact": "HIGH", "subAvailabilityImpact": "HIGH", "exploitMaturity": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "version": "4.0", "baseSeverity": "CRITICAL", "baseScore": 9.4, "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H"}, "format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "problemTypes": [{"descriptions": [{"cweId": "CWE-434", "description": "CWE-434 Unrestricted Upload of File with Dangerous Type", "lang": "en", "type": "CWE"}]}], "providerMetadata": {"orgId": "6ff30186-7fb7-4ad9-be33-533e7b05e586", "shortName": "Joomla", "dateUpdated": "2026-08-27T05:50:13.521Z"}, "references": [{"tags": ["product"], "url": "https://www.joomlaeventmanager.net/"}], "source": {"discovery": "UNKNOWN"}, "title": "Joomla Extension - joomlaeventmanager.net - Privileged remote code execution in Joomla Event Manager < 5.0.1", "x_generator": {"engine": "Vulnogram 0.1.0-dev"}}}}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "JEM - Joomla Event Manager extension for Joomla", "vendor": "joomlaeventmanager.net", "versions": [{"status": "affected", "version": "1.0.0-5.0.0"}]}], "source": "security@joomla.org"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Joomla Extension - joomlaeventmanager.net - Privileged remote code execution in Joomla Event Manager < 5.0.1 - The administrator source model allows to write dangerous file type incl. PHP, leading to remote code execution."}], "id": "CVE-2026-77991", "lastModified": "2026-08-27T06:17:28.970", "metrics": {"cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 9.4, "baseSeverity": "CRITICAL", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "HIGH", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "HIGH", "subConfidentialityImpact": "HIGH", "subIntegrityImpact": "HIGH", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "version": "4.0", "vulnAvailabilityImpact": "HIGH", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "security@joomla.org", "type": "Secondary"}]}, "published": "2026-08-27T06:17:28.970", "references": [{"source": "security@joomla.org", "url": "https://www.joomlaeventmanager.net/"}], "sourceIdentifier": "security@joomla.org", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-434"}], "source": "security@joomla.org", "type": "Primary"}]}