How severe is CVE-2026-18556?

CVE-2026-18556 has a CVSS 3.x base score of 7.4, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2026-18556 being actively exploited?

Yes. CVE-2026-18556 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2026-08-04, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2026-18556?

CVE-2026-18556 affects N-able N-central. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-18556?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

When was CVE-2026-18556 published?

CVE-2026-18556 was published on 2026-08-01 and last updated on 2026-08-05.

CVE-2026-18556

CVE-2026-18556 is a high-severity vulnerability in N-able N-central with a CVSS 3.x base score of 7.4. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2026-08-04). The underlying weakness is classified as CWE-288.

Key facts

Severity: High (CVSS 3.x base score 7.4)
CVSS v4: 8.2
EPSS exploit prediction: 0% (40th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2026-08-04)
Weakness: CWE-288
Affected product: N-able N-central
Published: 2026-08-01
Last modified: 2026-08-05

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.

Frequently asked questions

What is CVE-2026-18556?: 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.
How severe is CVE-2026-18556?: CVE-2026-18556 has a CVSS 3.x base score of 7.4, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2026-18556 being actively exploited?: Yes. CVE-2026-18556 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2026-08-04, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2026-18556?: CVE-2026-18556 affects N-able N-central. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-18556?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
When was CVE-2026-18556 published?: CVE-2026-18556 was published on 2026-08-01 and last updated on 2026-08-05.

References

Affected products (1)

cpe:2.3:a:n-able:n-central:*:*:*:*:*:*:*:*

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