Vulnerability

CVE-2026-18556

High· 7.4KEVCVSS7.4EPSS8%

.rules3/5

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

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

Threat signal

86/100

High

Severity

high

CVSS

7.4

EPSS

Active

KEV

CISA KEV — actively exploited

70d overdue

AffectedN-able — N-central

Added to KEV

2026-08-04

Federal patch due (BOD 22-01)

2026-08-07

Required action (CISA verbatim)

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.

Vendor advisory + references

CISA description: “N-able N-central contains an authentication bypass using an alternate path or channel that allows for authentication bypass.”

CVSS

v3.1via NVDOpen in FIRST calculator →

7.4/ 10HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

Attack VectorNetworkExploitable remotely over the internet — no local access needed.
Attack ComplexityHighRequires conditions outside attacker's control (race, brute-force, configuration
Privileges RequiredNoneUnauthenticated — no credentials needed.
User InteractionNoneFully automated — no victim action needed.
ScopeUnchangedImpact contained to the vulnerable component.
Confidentiality ImpactHighTotal disclosure of sensitive data.
Integrity ImpactHighTotal compromise of integrity — full data modification possible.
Availability ImpactNoneNo availability impact.

EPSS

Exploit prediction · 30-day horizonFIRST.org →

7.88%

probability of exploitation in next 30 days

p95

higher than 95% of all CVEs

3-day trend↑ 0pp

Mid-pack — moderate exploitation likelihood.

Vendor VEX

No VEX statements published for CVE-2026-18556. Vendors publish VEX (Vulnerability Exploitability eXchange) to assert per-product whether a CVE is actually exploitable in their distribution.

SSVCAct

Active exploitation with total impact on essential/support systems

exploitation: active
automatable: no
impact: total
mission: support

Lifecycle

2026-08-04Added to CISA KEVransomware: Unknown
2026-08-04Published
2026-08-04Last modified2 sources
2026-08-07Federal patch due (BOD 22-01)