CVE-2026-58058 Nmap - Integer Underflow in IPv6 Extension Header Parsing
An attacker can cause a crash in Nmap by sending crafted IPv6 responses during scans, due to an integer underflow in extension header parsing.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-58058?
CVE-2026-58058 is a medium-severity vulnerability in Nmap, published on 28 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-191
Which versions are affected by CVE-2026-58058?
It affects 1 product.
Linux distribution packages (6)
nmap SUSE:Linux Enterprise Module for Basesystem 15 SP7 | All versions | 7.92-150600.9.3.1 |
nmap SUSE:Linux Enterprise Module for Package Hub 15 SP7 | All versions | 7.92-150600.9.3.1 |
nmap SUSE:Linux Enterprise Server 16.0 | All versions | 7.92-160000.3.1 |
nmap SUSE:Linux Enterprise Server LTSS Extended Security 12 SP5 | All versions | 6.46-3.9.1 |
nmap SUSE:Linux Enterprise Server for SAP applications 16.0 | All versions | 7.92-160000.3.1 |
nmap SUSE:Linux Micro Extras 6.2 | All versions | 7.92-160000.3.1 |
Products include Nmap Nmap.
How do I fix CVE-2026-58058?
Apply the vendor's patch.
Is CVE-2026-58058 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-58058 exists.
Public exploit code: 1 Exploit-DB entry.
Other vulnerabilities in Nmap
Sources
Also known as AZL-91391, CLSA-2026-1788628939, CLSA-2026-1788629925, DEBIAN-CVE-2026-58058, ECHO-c25e-3693-b903, GHSA-wxvj-hc4r-fq45 and 12 more.