Vulnerability report

Exploited in the wild Confirmed confidence In CISA KEV

CVE-2026-18556

Unauthenticated administrative account takeover

N-able / N-central · 0 to <= 2026.1

Severity
CVSS 8.2 · High
Confidence
Confirmed
Exploit status
Exploited in the wild
EPSS
0.5%
First observed
Last observed

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2026-18556 is an unauthenticated Unauthenticated administrative account takeover affecting N-able N-central. Authentication bypass using an alternate path or channel vulnerability in N-able N-central allows...

Is it exploited?

Yes. KEV Intelligence tracks this CVE as a known exploited vulnerability. Confidence is confirmed.

Who is affected?

N-able / N-central 0 to <= 2026.1.

What should we do?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Overview

Authentication bypass using an alternate path or channel vulnerability in N-able N-central allows Authentication Bypass

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.

Vendor Product Affected Status
N-able N-central Through 2026.1 Affected
Published
01 Aug 2026
Exploitation Reported
01 Aug 2026
Attack vector
Remote
Complexity
High
Privileges
None
User interaction
None

Tags

cisa

CVE References

  • CVE Record CVE.org · CVE Record https://www.cve.org/CVERecord?id=CVE-2026-18556
  • uptime.n-able.com uptime.n-able.com · CVE Record https://uptime.n-able.com/

Exploitation evidence

Why KEV Intelligence marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

KEV Intelligence

Recorded 01 Aug 2026

Independent exploitation attestation added to the KEV Intelligence record.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the KEV Intelligence Pro API.

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Source Added
KEV Intelligence First 2026-08-01 13:51 UTC
TheHackerNews 2026-08-04 07:00 UTC
Rapid7 2026-08-04 11:11 UTC
CISA 2026-08-04 16:45 UTC
CVE 2026-08-04 18:20 UTC

Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
0
User-Agents
0

Raw values available in Pro and Enterprise.

Scanner coverage

No scanner integrations recorded yet.

Virtual patch status

No KEV Intelligence virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

No detection artifacts or sensor request patterns are available for this CVE yet.

Check back as sensor telemetry and scanner integrations are updated.

Risk and context

Severity, weaknesses, and research context

CVSS v4.0

8.2 High
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

EPSS

0.5%

Recent mention · Rapid7

CVE-2026-18577: N-able N-central Authentication Bypass Exploited in the Wild

OverviewOn August 2, 2026, N-able published a security advisory for CVE-2026-18577, an authentication bypass vulnerability affecting N-central that was discovered being exploited in-the-wild after an incomplete fix for an earlier authentication bypass issue, CVE-2026-18556 was...

Read full advisory

All CVSS Scores

CVSS v4.0 8.2 High

CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

CVSS v3.1 7.4 High

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

All Mentions

Recent mention · Rapid7

CVE-2026-18577: N-able N-central Authentication Bypass Exploited in the Wild

Rapid7 · 04 Aug 2026

OverviewOn August 2, 2026, N-able published a security advisory for CVE-2026-18577, an authentication bypass vulnerability affecting N-central that was discovered being exploited in-the-wild after an incomplete fix for an earlier authentication bypass issue, CVE-2026-18556 was disclosed. CVE-2026-18577 allows a remote unauthenticated attacker to bypass authentication and obtain administrative control of vulnerable N-central servers in affected deployments.N-able N-central is a widely deployed Remote Monitoring and Management (RMM) platform used by managed service providers (MSPs) and...

Recent mention · TheHackerNews

CISA Adds Exploited N-able N-central Flaw to KEV After Customer Compromises

TheHackerNews · 04 Aug 2026

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) on Monday added a high-severity security flaw impacting N-able N-central to its Known Exploited Vulnerabilities (KEV) catalog following reports of active exploitation in the wild. The vulnerability, tracked as CVE-2026-18577 (CVSS score: 8.2), is a case of incomplete patching for CVE-2026-18556 (CVSS score: 8.2) that allows

Timeline

From disclosure to observed exploitation

  1. KEV confirmed by CVE

    Exploitation attested by an external source

  2. Added to CISA KEV

    Listed in the CISA Known Exploited Vulnerabilities catalog

  3. KEV confirmed by Rapid7

    Exploitation attested by an external source

  4. KEV confirmed by TheHackerNews

    Exploitation attested by an external source

  5. CVE published

    Vulnerability disclosed publicly

  6. Added to KEV Intelligence KEV Feed

    High-confidence, third-party attested exploitation

  7. CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2026-18556

Free JSON includes basic KEV fields
{
  "cve_id": "CVE-2026-18556",
  "confidence": "Confirmed",
  "cvss_score": 8.2,
  "cvss_estimated": false,
  "epss_score": 0.00492,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}

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