Actively exploited · Published Aug 2, 2026 · Assigned by N-able
CVE-2026-18577Incomplete patch leads to administrative account takeover
High 8.2 Exploited
In plain English
A high-severity authentication bypass in N-central from N-able. Attackers are actively exploiting it in the wild (listed by CISA on August 3, 2026). The chance it is exploited in the next 30 days is estimated at 14.6% (higher than 97% of all known vulnerabilities). Ready-made attack tooling exists: Nuclei, public proof-of-concept code. 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.
CISA guidance
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.
Federal agencies must remediate by Aug 6, 2026.
Official description
An incomplete patch for CVE-2026-18556 allows for authentication bypass and account takeover in N-central Versions through 2026.3.1
Affected products (as reported)
Weakness: CWE-288 · Vector: CVSS: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
References
- 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/
- https://www.cve.org/CVERecord?id=CVE-2026-18556
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-18577 government-resource
- https://www.n-able.com/blog/n-central-security-update-august-2-2026 vendor-advisory