CVE-2026-58058

MEDIUMPre-NVD 6.56.5—
EchelonGraph scoreMEDIUM confidence

Score 6.5 from GitHub Security Advisory published 2026-06-28. a secondary CVSS source baseline 6.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this weekElevated
6.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 6.5Exploit: Elevated riskExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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
EG Score
6.5(medium)
EG Risk
60(Attend)
EG Risk 60/100SSVC: Attend

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity65% × 45%
Exploitation40% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
1%
EPSS %ILE
70%
KEV
Not listed

Published

June 28, 2026

Last Modified

June 30, 2026

Advisory Details (4)

Auto-updated Jun 28, 2026
🔬 Proof of concept available. Upstream fix merged — awaiting tagged release. Sources: github_commit.
generic🟡 PoC Available

Nmap - Integer Underflow in IPv6 Extension Header Parsing | Advisories | VulnCheck

https://www.vulncheck.com/advisories/nmap-integer-underflow-in-ipv6-extension-header-parsing
generic

Nmap Change Log

https://nmap.org/changelog.html
github_commit

commit bb6754e76bb1 (nmap/nmap)

Fix landed in nmap/nmap commit bb6754e76bb1 — awaiting tagged release

https://github.com/nmap/nmap/commit/bb6754e76bb1686315008e1aa1c40202a513fb83
generic🟡 PoC Available

exploitarium/nmap-ipv6-extlen-wrap-poc at main · bikini/exploitarium · GitHub

https://github.com/bikini/exploitarium/tree/main/nmap-ipv6-extlen-wrap-poc

Vendor Advisories for CVE-2026-58058(2)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
nmap7.91+dfsg1+really7.80+dfsg1-2 ... 7.99+dfsg-2 (25 versions)——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
nmap7.93+dfsg1-1 ... 7.99+dfsg-2 (20 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
nmap7.95+dfsg-3, 7.98+dfsg-1, 7.98+dfsg-1~bpo13+1, 7.99+dfsg-1, 7.99+dfsg-2——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
nmap7.95+dfsg-3, 7.98+dfsg-1, 7.98+dfsg-1~bpo13+1, 7.99+dfsg-17.99+dfsg-2—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 8× in last 7d / 65× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 200 total refreshes for this CVE.

  1. 2026-09-11 14:53 UTCEPSS rescore
  2. 2026-09-10 09:35 UTCEPSS rescore
  3. 2026-09-08 22:01 UTCEPSS rescore
  4. 2026-09-07 16:01 UTCEPSS rescore
  5. 2026-09-06 14:48 UTCEG score recompute
  6. 2026-09-06 14:48 UTCVendor advisory
  7. 2026-09-06 14:48 UTCGHSA enrichment
  8. 2026-09-06 13:47 UTCEPSS rescore
  9. 2026-09-04 05:07 UTCEPSS rescore
  10. 2026-09-02 14:12 UTCEPSS rescore
  11. 2026-09-01 13:54 UTCEPSS rescore
  12. 2026-09-01 04:40 UTCEPSS rescore
  13. 2026-08-30 19:17 UTCEPSS rescore
  14. 2026-08-30 19:11 UTCEG score recompute
  15. 2026-08-30 19:11 UTCVendor advisory
  16. 2026-08-30 19:11 UTCGHSA enrichment
  17. 2026-08-30 01:22 UTCEPSS rescore
  18. 2026-08-28 21:42 UTCEPSS rescore
  19. 2026-08-27 22:51 UTCEG score recompute
  20. 2026-08-27 22:51 UTCVendor advisory
  21. 2026-08-27 22:51 UTCGHSA enrichment
  22. 2026-08-27 14:25 UTCEPSS rescore
  23. 2026-08-26 14:46 UTCEPSS rescore
  24. 2026-08-25 13:49 UTCEPSS rescore
  25. 2026-08-24 12:44 UTCEG score recompute
Show 75 more
  1. 2026-08-24 12:44 UTCVendor advisory
  2. 2026-08-24 12:44 UTCGHSA enrichment
  3. 2026-08-23 09:57 UTCEG score recompute
  4. 2026-08-23 09:57 UTCVendor advisory
  5. 2026-08-23 09:57 UTCGHSA enrichment
  6. 2026-08-23 00:19 UTCEPSS rescore
  7. 2026-08-22 09:14 UTCEG score recompute
  8. 2026-08-22 09:14 UTCVendor advisory
  9. 2026-08-22 09:14 UTCGHSA enrichment
  10. 2026-08-21 23:49 UTCEPSS rescore
  11. 2026-08-21 06:45 UTCEG score recompute
  12. 2026-08-21 06:45 UTCVendor advisory
  13. 2026-08-21 06:45 UTCGHSA enrichment
  14. 2026-08-20 22:55 UTCEPSS rescore
  15. 2026-08-20 06:02 UTCEG score recompute
  16. 2026-08-20 06:02 UTCGHSA enrichment
  17. 2026-08-19 17:04 UTCEPSS rescore
  18. 2026-08-18 23:24 UTCEG score recompute
  19. 2026-08-18 23:23 UTCGHSA enrichment
  20. 2026-08-18 13:48 UTCEPSS rescore
  21. 2026-08-17 17:00 UTCEG score recompute
  22. 2026-08-17 17:00 UTCVendor advisory
  23. 2026-08-17 17:00 UTCGHSA enrichment
  24. 2026-08-17 13:47 UTCEPSS rescore
  25. 2026-08-16 16:17 UTCEG score recompute
  26. 2026-08-16 16:17 UTCVendor advisory
  27. 2026-08-16 16:17 UTCGHSA enrichment
  28. 2026-08-16 14:56 UTCEPSS rescore
  29. 2026-08-16 02:14 UTCEPSS rescore
  30. 2026-08-15 15:34 UTCEG score recompute
  31. 2026-08-15 15:34 UTCVendor advisory
  32. 2026-08-15 15:34 UTCGHSA enrichment
  33. 2026-08-15 01:30 UTCEPSS rescore
  34. 2026-08-14 14:50 UTCEG score recompute
  35. 2026-08-14 14:50 UTCVendor advisory
  36. 2026-08-14 14:50 UTCGHSA enrichment
  37. 2026-08-13 22:00 UTCEPSS rescore
  38. 2026-08-13 14:07 UTCEG score recompute
  39. 2026-08-13 14:07 UTCVendor advisory
  40. 2026-08-13 14:07 UTCGHSA enrichment
  41. 2026-08-12 13:51 UTCEPSS rescore
  42. 2026-08-12 13:16 UTCEG score recompute
  43. 2026-08-12 13:16 UTCVendor advisory
  44. 2026-08-12 13:16 UTCGHSA enrichment
  45. 2026-08-11 12:32 UTCEG score recompute
  46. 2026-08-11 12:32 UTCVendor advisory
  47. 2026-08-11 12:32 UTCGHSA enrichment
  48. 2026-08-11 00:00 UTCEPSS rescore
  49. 2026-08-10 11:49 UTCEG score recompute
  50. 2026-08-10 11:49 UTCGHSA enrichment
  51. 2026-08-09 13:46 UTCEPSS rescore
  52. 2026-08-09 11:07 UTCEG score recompute
  53. 2026-08-09 11:07 UTCVendor advisory
  54. 2026-08-09 11:07 UTCGHSA enrichment
  55. 2026-08-08 16:37 UTCEPSS rescore
  56. 2026-08-08 10:24 UTCEG score recompute
  57. 2026-08-08 10:24 UTCVendor advisory
  58. 2026-08-08 10:24 UTCGHSA enrichment
  59. 2026-08-07 09:41 UTCEG score recompute
  60. 2026-08-07 09:41 UTCVendor advisory
  61. 2026-08-07 09:41 UTCGHSA enrichment
  62. 2026-08-06 13:47 UTCEPSS rescore
  63. 2026-08-06 08:58 UTCEG score recompute
  64. 2026-08-06 08:58 UTCVendor advisory
  65. 2026-08-06 08:58 UTCGHSA enrichment
  66. 2026-08-05 19:17 UTCEPSS rescore
  67. 2026-08-05 08:16 UTCEG score recompute
  68. 2026-08-05 08:16 UTCVendor advisory
  69. 2026-08-05 08:15 UTCGHSA enrichment
  70. 2026-08-04 15:10 UTCEPSS rescore
  71. 2026-08-04 10:39 UTCEPSS rescore
  72. 2026-08-04 04:17 UTCEG score recompute
  73. 2026-08-04 04:16 UTCGHSA enrichment
  74. 2026-08-03 10:36 UTCEPSS rescore
  75. 2026-08-03 03:33 UTCVendor advisory

Publicly available exploits

(1 reference)

Working exploit code is in the public domain (1 Exploit-DB entry). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • Exploit-DBEDB-52647
    First seen Aug 17, 2026

    Nmap 7.99 - Extension Header Integer Underflow

    Open source ↗

Frequently asked(5)

What is CVE-2026-58058?
CVE-2026-58058 is a medium vulnerability published on June 28, 2026. Nmap through 7.99 does not keep the IPv6 extension-header walk within the captured packet in ipv6getdata_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…
When was CVE-2026-58058 disclosed?
CVE-2026-58058 was first published in the National Vulnerability Database on June 28, 2026, with the most recent update on June 30, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-58058 actively exploited?
CVE-2026-58058 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 29.8% of all scored CVEs.
What is the CVSS score of CVE-2026-58058?
CVE-2026-58058 has a CVSS v3 base score of 6.5 (NVD).
How do I remediate CVE-2026-58058?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-58058, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-58058

Explore →

Is Your Infrastructure Affected by CVE-2026-58058?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs