CVE-2026-18556

CRITICALNVD 7.49.0▲
EchelonGraph scoreHIGH confidence

Score elevated to 9.0 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2026-08-04), indicating real-world exploitation has been confirmed by US federal agencies. NVD baseline CVSS 7.4 retained for reference. Confidence: HIGH.

Triggered by: CISA KEV (actively exploited)
Sources: cisa_kev, epss, ghsa, nvd
Trending — 4 sources updated this weekExploited in the wild
9.0EG
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV)
CISA-KEV: ExploitedEPSS PROB: 40%CVSS: 7.4Exploit: cisa kev · ssvc active · epss top5pctExposed: 0

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

Authentication bypass using an alternate path or channel vulnerability in N-able N-central allows Authentication Bypass.

This issue affects N-central: through 2026.1.

CVSS v3
7.4
EG Score
9.0(high)
EG Risk
96(Act)
EG Risk 96/100SSVC: Act

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
Severity90% × 45%
Exploitation100% × 40%
Automatability100% × 15%
Action: Fix now — active exploitation, automatable, high impact.
EPSS PROB
40%
EPSS %ILE
99%
KEV
⚠ Exploited

Published

August 1, 2026

Last Modified

August 5, 2026

Advisory Details (1)

Auto-updated Aug 1, 2026
No patch confirmed yet.
generic

Status Dashboard

https://uptime.n-able.com/

Vendor Advisories for CVE-2026-18556(1)

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

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 56× in last 7d / 246× 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 410 total refreshes for this CVE.

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

Frequently asked(6)

What is CVE-2026-18556?
CVE-2026-18556 is a critical vulnerability published on August 1, 2026. Authentication bypass using an alternate path or channel vulnerability in N-able N-central allows Authentication Bypass. This issue affects N-central: through 2026.1.
When was CVE-2026-18556 disclosed?
CVE-2026-18556 was first published in the National Vulnerability Database on August 1, 2026, with the most recent update on August 5, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-18556 actively exploited?
Yes. CISA added CVE-2026-18556 to the Known Exploited Vulnerabilities catalog on August 4, 2026, affecting N-able N-central. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate patching attention.
What is the CVSS score of CVE-2026-18556?
CVE-2026-18556 has a CVSS v3 base score of 7.4 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.0.
Which products are affected by CVE-2026-18556?
CVE-2026-18556 affects N-able N-central. The full affected-products list, including version ranges and fixed versions, is shown in the Affected Packages section of this page.
How do I remediate CVE-2026-18556?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-18556, 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

Explore the affected products and dependency analysis for CVE-2026-18556

Explore →

Is Your Infrastructure Affected by CVE-2026-18556?

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

Start Free Scan →Browse All CVEs