CVE-2026-27760

OpenCATS prior to commit 3002a29 contains a PHP code injection vulnerability in the installer AJAX endpoint that allows unauthenticated attackers to execute arbitrary code by injecting PHP statements into the databaseConnectivity action parameter. Attackers can break out of the define() string context in config.php using a single quote and statement separator to inject malicious PHP code that persists and executes on every subsequent page load when the installation wizard remains incomplete.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://chocapikk.com/posts/2026/opencats-installer-rce/
https://github.com/opencats/OpenCATS/blob/46e4727/lib/CATSUtility.php#L142-L172
https://github.com/opencats/OpenCATS/blob/46e4727/modules/install/ajax/ui.php#L130
https://github.com/opencats/OpenCATS/commit/3002a29f4c3cada1aa2c4f3d4ae4e189906606b6
https://github.com/opencats/OpenCATS/pull/706
https://www.vulncheck.com/advisories/opencats-php-code-injection-via-installer-ajax-endpoint

Configurations

No configuration.

History

No history.

Information

Published : 2026-04-28 15:16

Updated : 2026-07-14 19:16

NVD link : CVE-2026-27760

Mitre link : CVE-2026-27760

CVE.ORG link : CVE-2026-27760

JSON object : View

Products Affected

No product.

CWE

CWE-94

Improper Control of Generation of Code ('Code Injection')

{"id": "CVE-2026-27760", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-27760", "role": "CISA Coordinator", "options": [{"exploitation": "poc"}, {"automatable": "no"}, {"technicalImpact": "total"}], "version": "2.0.3", "timestamp": "2026-04-28T14:55:56.133961Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 8.1, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 2.2}], "cvssMetricV40": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 9.2, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/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", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "NONE", "attackComplexity": "HIGH", "attackRequirements": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "HIGH", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "HIGH", "confidentialityRequirement": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED"}}]}, "affected": [{"source": "disclosure@vulncheck.com", "affectedData": [{"repo": "https://github.com/opencats/OpenCATS", "vendor": "opencats", "product": "OpenCATS", "versions": [{"status": "affected", "version": "0", "versionType": "custom", "lessThanOrEqual": "0.9.7.4"}, {"status": "unaffected", "version": "3002a29f4c3cada1aa2c4f3d4ae4e189906606b6", "versionType": "git"}], "packageURL": "pkg:github/opencats/OpenCATS", "defaultStatus": "unaffected"}]}], "published": "2026-04-28T15:16:26.800", "references": [{"url": "https://chocapikk.com/posts/2026/opencats-installer-rce/", "source": "disclosure@vulncheck.com"}, {"url": "https://github.com/opencats/OpenCATS/blob/46e4727/lib/CATSUtility.php#L142-L172", "source": "disclosure@vulncheck.com"}, {"url": "https://github.com/opencats/OpenCATS/blob/46e4727/modules/install/ajax/ui.php#L130", "source": "disclosure@vulncheck.com"}, {"url": "https://github.com/opencats/OpenCATS/commit/3002a29f4c3cada1aa2c4f3d4ae4e189906606b6", "source": "disclosure@vulncheck.com"}, {"url": "https://github.com/opencats/OpenCATS/pull/706", "source": "disclosure@vulncheck.com"}, {"url": "https://www.vulncheck.com/advisories/opencats-php-code-injection-via-installer-ajax-endpoint", "source": "disclosure@vulncheck.com"}], "vulnStatus": "Deferred", "weaknesses": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "description": [{"lang": "en", "value": "CWE-94"}]}], "descriptions": [{"lang": "en", "value": "OpenCATS prior to commit 3002a29 contains a PHP code injection vulnerability in the installer AJAX endpoint that allows unauthenticated attackers to execute arbitrary code by injecting PHP statements into the databaseConnectivity action parameter. Attackers can break out of the define() string context in config.php using a single quote and statement separator to inject malicious PHP code that persists and executes on every subsequent page load when the installation wizard remains incomplete."}], "lastModified": "2026-07-14T19:16:53.277", "sourceIdentifier": "disclosure@vulncheck.com"}