CVE-2026-18556 - N-able N-central Authentication Bypass Using an Alternate Path or Channel Vulnerability

Technical Severity

CVSS v3.1 Metrics

HIGH

7.4 / 10

Minimal Risk Critical

Vector Specification

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

Exploitation Likelihood

EPSS Prediction

40.16 %

Predictive Probability

Percentile Rank

98.5 th

Documented as more likely to be exploited than 98.5% of known CVEs.

Detection Date

Aug 04, 2026

Remediation Due

Aug 07, 2026

CISA Catalog Active

Threat Analysis

N-able N-central contains an authentication bypass using an alternate path or channel that allows for authentication bypass.

Remediation Directive

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.

External Intelligence

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

https://status.n-able.com/2026/08/02/n-central-2026-3-hotfix-1-mitigation-for-cve-2026-18577/

CISA

CISA Advisory

https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk

CISA

CISA Advisory

https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk

NVD

National Vulnerability Database

https://nvd.nist.gov/vuln/detail/CVE-2026-18556