How severe is CVE-2026-58058?

CVE-2026-58058 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability low.

Is CVE-2026-58058 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-58058?

CVE-2026-58058 affects Nmap. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-58058?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2026-58058 published?

CVE-2026-58058 was published on 2026-06-28 and last updated on 2026-06-30.

CVE-2026-58058

CVE-2026-58058 is a medium-severity vulnerability in Nmap with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-191.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v4: 6.9
EPSS exploit prediction: 0% (20th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-191
Affected product: Nmap
Published: 2026-06-28
Last modified: 2026-06-30

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.

Frequently asked questions

What is 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.
How severe is CVE-2026-58058?: CVE-2026-58058 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability low.
Is CVE-2026-58058 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-58058?: CVE-2026-58058 affects Nmap. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-58058?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-58058 published?: CVE-2026-58058 was published on 2026-06-28 and last updated on 2026-06-30.

References

Affected products (1)

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

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