CVE-2026-18577
N-able N-central Authentication Bypass Using an Alternate Path or Channel Vulnerability
Does this matter?
Known to be exploited in the wild (CISA KEV, CISA remediation deadline 6 August 2026). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.
Description
An incomplete patch for CVE-2026-18556 allows for authentication bypass and account takeover in N-central Versions through 2026.3.1
- CVSS 4.0
- 8.2 HIGHCVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:L/SI:L/SA:L/E:A/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 54.07% probability · 99th percentile
- CISA KEV
- Listed 3 August 2026 · due 6 August 2026
- Weakness
- CWE-288
- Affected
- n-able/n-central
- Source
- a5532a13-c4dd-4202-bef1-e0b8f2f8d12b
CISA notes
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. https://documentation.n-able.com/N-central/Release_Notes/GA/Content/N-central_2026.3_HF1_Release_Notes.htm ; 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-2026-18577
References
- https://documentation.n-able.com/N-central/Release_Notes/GA/Content/N-central_2026.3_HF1_Release_Notes.htmPatch, Release Notes
- https://status.n-able.com/2026/08/02/n-central-2026-3-hotfix-1-mitigation-for-cve-2026-18577/Release Notes
- https://www.cve.org/CVERecord?id=CVE-2026-18556VDB Entry
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-18577US Government Resource
- https://www.n-able.com/blog/n-central-security-update-august-2-2026Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.