{"id":"CVE-2026-58058","summary":"Nmap - Integer Underflow in IPv6 Extension Header Parsing","details":"Nmap through 7.99 does not keep the IPv6 extension-header walk within the captured packet in ipv6_get_data_primitive (libnetutil/netutil.cc), so the pointer advances past the buffer and the remaining-length computation underflows to a large value. A scanned target or on-path attacker returning a crafted IPv6 response with a truncated extension header can trigger out-of-bounds reads and a crash during raw IPv6 scans.","modified":"2026-08-15T00:25:11.143936Z","published":"2026-06-28T01:32:59.336Z","related":["SUSE-SU-2026:22739-1","SUSE-SU-2026:22814-1","SUSE-SU-2026:3333-1","SUSE-SU-2026:3340-1"],"database_specific":{"cwe_ids":["CWE-191"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/58xxx/CVE-2026-58058.json","cna_assigner":"VulnCheck"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/58xxx/CVE-2026-58058.json"},{"type":"ADVISORY","url":"https://nmap.org/changelog.html"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-58058"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/nmap-integer-underflow-in-ipv6-extension-header-parsing"},{"type":"FIX","url":"https://github.com/nmap/nmap/commit/bb6754e76bb1686315008e1aa1c40202a513fb83"},{"type":"EVIDENCE","url":"https://github.com/bikini/exploitarium/tree/main/nmap-ipv6-extlen-wrap-poc"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/nmap/nmap","events":[{"introduced":"0"},{"fixed":"bb6754e76bb1686315008e1aa1c40202a513fb83"}],"database_specific":{"cpe":"cpe:2.3:a:nmap:nmap:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"0"},{"last_affected":"7.99"}],"source":["CPE_RANGE","REFERENCES"]}}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-58058.json","vanir_signatures_modified":"2026-08-15T00:25:11Z","vanir_signatures":[{"id":"CVE-2026-58058-02ef1481","signature_type":"Line","signature_version":"v1","source":"https://github.com/nmap/nmap/commit/bb6754e76bb1686315008e1aa1c40202a513fb83","target":{"file":"libnetutil/netutil.cc"},"deprecated":false,"digest":{"line_hashes":["145508270917644213296583443907588523399","96563822267243935670484602926712022871","124043627670187252626341567966163749908","281406455622579882127987983584235823092","240658403601090996670433758407496718041","322081025817709380104446581397967329226","24930405134028693560859293211274131987","143362629384587272283727625953474409106"],"threshold":0.9}},{"source":"https://github.com/nmap/nmap/commit/bb6754e76bb1686315008e1aa1c40202a513fb83","target":{"file":"libnetutil/netutil.cc","function":"ipv6_get_data_primitive"},"deprecated":false,"digest":{"function_hash":"137564203164912028897199334127478259627","length":529},"id":"CVE-2026-58058-95973e34","signature_type":"Function","signature_version":"v1"}]}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N"}]}