{"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":"2026-07-08T08:13:48.021515669Z","published":"2026-06-28T01:32:59.336Z","database_specific":{"unresolved_ranges":[{"source":"AFFECTED_FIELD","extracted_events":[{"last_affected":"7.99"}]},{"source":"CPE_FIELD","extracted_events":[{"last_affected":"7.99"}]},{"source":"DESCRIPTION","extracted_events":[{"fixed":"7.99"}]}],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/58xxx/CVE-2026-58058.json","cwe_ids":["CWE-191"],"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":{"source":"REFERENCES"}}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-58058.json"}}],"schema_version":"1.7.5","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"}]}