CVE-2026-58058

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 v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/bikini/exploitarium/tree/main/nmap-ipv6-extlen-wrap-poc	Broken Link
https://github.com/nmap/nmap/commit/bb6754e76bb1686315008e1aa1c40202a513fb83	Patch
https://nmap.org/changelog.html	Patch Release Notes
https://www.vulncheck.com/advisories/nmap-integer-underflow-in-ipv6-extension-header-parsing	Patch Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:nmap:nmap:*:*:*:*:*:*:*:*

History

30 Jun 2026, 17:31

Type	Values Removed	Values Added
References	~~() https://github.com/bikini/exploitarium/tree/main/nmap-ipv6-extlen-wrap-poc -~~	() https://github.com/bikini/exploitarium/tree/main/nmap-ipv6-extlen-wrap-poc - Broken Link
References	~~() https://github.com/nmap/nmap/commit/bb6754e76bb1686315008e1aa1c40202a513fb83 -~~	() https://github.com/nmap/nmap/commit/bb6754e76bb1686315008e1aa1c40202a513fb83 - Patch
References	~~() https://nmap.org/changelog.html -~~	() https://nmap.org/changelog.html - Patch, Release Notes
References	~~() https://www.vulncheck.com/advisories/nmap-integer-underflow-in-ipv6-extension-header-parsing -~~	() https://www.vulncheck.com/advisories/nmap-integer-underflow-in-ipv6-extension-header-parsing - Patch, Third Party Advisory
CPE		cpe:2.3:a:nmap:nmap::::::::
First Time		Nmap Nmap nmap

28 Jun 2026, 02:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-28 02:16

Updated : 2026-06-30 17:31

NVD link : CVE-2026-58058

Mitre link : CVE-2026-58058

CVE.ORG link : CVE-2026-58058

JSON object : View

Products Affected

nmap

nmap

CWE

CWE-191

Integer Underflow (Wrap or Wraparound)

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