CVEs / CVE-2026-18577
CVE-2026-18577: N-able N-central Authentication Bypass Using an Alternate Path or Channel Vulnerability
- Known exploited in the CISA KEV catalog since 3 Aug 2026
- high 8.1 CVSS 3.1 (NVD)
- EPSS 14.6% chance of exploitation in the next 30 days, higher than 96% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
N-able N-central contains an authentication bypass using an alternate path or channel allows for authentication bypass and account takeover in N-central. This vulnerability is the result of an incomplete patch for CVE-2026-18556.
Description
An incomplete patch for CVE-2026-18556 allows for authentication bypass and account takeover in N-central Versions through 2026.3.1
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| N-able N-central | up to and including 2026.3 | — |
Exploitation
| In CISA KEV since | 3 Aug 2026 |
|---|---|
| Due date for US federal agencies | 6 Aug 2026 |
| Used in ransomware campaigns | Unknown |
| 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. |
Severity
| CVSS 3.1 | 8.1 highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:HScored by NVD |
|---|---|
| Weakness | CWE-288 |
References
- CVE-2026-18577 on NVD
- CVE-2026-18577 in the CISA KEV catalog
- https://documentation.n-able.com/N-central/Release_Notes/GA/Content/N-central_2026.3_HF1_Release_Notes.htm (cited by CISA)
- https://status.n-able.com/2026/08/02/n-central-2026-3-hotfix-1-mitigation-for-cve-2026-18577/ (cited by CISA)
- https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk (cited by CISA)
- https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk (cited by CISA)
- https://documentation.n-able.com/N-central/Release_Notes/GA/Content/N-central_2026.3_HF1_Release_Notes.htm Patch, 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-2026-18556 VDB Entry
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-18577 US Government Resource
- https://www.n-able.com/blog/n-central-security-update-august-2-2026 Vendor Advisory
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.