Vulnerability Description
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.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://github.com/bikini/exploitarium/tree/main/nmap-ipv6-extlen-wrap-poc
- https://github.com/nmap/nmap/commit/bb6754e76bb1686315008e1aa1c40202a513fb83
- https://nmap.org/changelog.html
- https://www.vulncheck.com/advisories/nmap-integer-underflow-in-ipv6-extension-he
FAQ
What is CVE-2026-58058?
CVE-2026-58058 is a vulnerability with a CVSS score of 6.5 (MEDIUM). 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-...
How severe is CVE-2026-58058?
CVE-2026-58058 has been rated MEDIUM with a CVSS base score of 6.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-58058?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.