Unauthenticated administrative account takeover
Summary
| CVE | CVE-2026-18556 |
|---|---|
| State | PUBLISHED |
| Assigner | N-able |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-08-01 20:16:37 UTC |
| Updated | 2026-08-05 05:16:46 UTC |
| Description | 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. |
Risk And Classification
Primary CVSS: v4.0 8.2 HIGH from a5532a13-c4dd-4202-bef1-e0b8f2f8d12b
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS: 0.401580000 probability, percentile 0.985840000 (date 2026-09-05)
CISA KEV: Listed on 2026-08-04; due 2026-08-07; ransomware use Unknown
Problem Types: CWE-288 | CWE-288 CWE-288 Authentication bypass using an alternate path or channel
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | a5532a13-c4dd-4202-bef1-e0b8f2f8d12b | Secondary | 8.2 | HIGH | CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/C... |
| 4.0 | CNA | CVSS | 8.2 | HIGH | CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N |
| 3.1 | [email protected] | Primary | 7.4 | HIGH | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N |
CVSS v4.0 Breakdown
Attack Vector
NetworkAttack Complexity
HighAttack Requirements
NonePrivileges Required
NoneUser Interaction
NoneConfidentiality
HighIntegrity
NoneAvailability
NoneSub Conf.
NoneSub Integrity
NoneSub Availability
NoneCVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
HighPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
NoneCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
CISA Known Exploited Vulnerability
| Vendor | N-able |
|---|---|
| Product | N-central |
| Name | N-able N-central Authentication Bypass Using an Alternate Path or Channel Vulnerability |
| Required Action | Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines. |
| Notes | https://uptime.n-able.com/ ; https://status.n-able.com/2026/08/02/n-central-2026-3-hotfix-1-mitigation-for-cve-2026-18577/ ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-18556 |
NVD Known Affected Configurations (CPE 2.3)
Vendor Declared Affected Products
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| uptime.n-able.com | a5532a13-c4dd-4202-bef1-e0b8f2f8d12b | uptime.n-able.com | Vendor Advisory |
| www.n-able.com/blog/n-central-security-update-august-2-2026 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | www.n-able.com | Vendor Advisory |
| www.cisa.gov/known-exploited-vulnerabilities-catalog | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | www.cisa.gov | US Government Resource |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
| CISA Known Exploited Vulnerabilities catalog | CISA | www.cisa.gov | kev |
No vendor comments have been submitted for this CVE.
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| ADP | 2026-08-04T00:00:00.000Z | CVE-2026-18556 added to CISA KEV |
There are currently no legacy QID mappings associated with this CVE.