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Known Exploited Vulnerability
8.2
HIGH CVSS 4.0
CVE-2026-18556
N-able N-central Authentication Bypass Using an Alternate Path or Channel Vulnerability - [Actively Exploited]
Overview
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.

Details
INFO

Published Date :

Aug. 1, 2026, 8:16 p.m.

Last Modified :

Aug. 5, 2026, 5:16 a.m.

Remotely Exploit :

Yes !

Source :

a5532a13-c4dd-4202-bef1-e0b8f2f8d12b
CISA Notification
CISA KEV (Known Exploited Vulnerabilities)

For the benefit of the cybersecurity community and network defenders—and to help every organization better manage vulnerabilities and keep pace with threat activity—CISA maintains the authoritative source of vulnerabilities that have been exploited in the wild.

Description :

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

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.

Known Ransomware Campaign Use:

Unknown

Notes :

https://uptime.n-able.com/ ; https://status.n-able.com/2026/08/02/n-central-2026-3-hotfix-1-mitigation-for-cve-2026-18577/ ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-18556

Impact
Affected Products

The following products are affected by CVE-2026-18556 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 N-able n-central
: Total Affected Vendor : 1 | Products : 1
Scoring
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 HIGH [email protected]
CVSS 4.0 HIGH a5532a13-c4dd-4202-bef1-e0b8f2f8d12b
CVSS 4.0 HIGH a5532a13-c4dd-4202-bef1-e0b8f2f8d12b
Solution
Update N-able N-central to the latest version to fix authentication bypass.
  • Update N-able N-central to the latest version.
  • Ensure alternate paths are secured.
  • Implement strict access controls.
References
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-18556.

URL Resource
https://uptime.n-able.com/ Vendor Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-18556 US Government Resource
https://www.n-able.com/blog/n-central-security-update-august-2-2026 Vendor Advisory
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-18556 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-18556 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-18556 vulnerability anywhere in the article.

  • security.nl
Australië waarschuwt bedrijven voor aanvallen op N-central RMM-servers

De Australische overheid waarschuwt bedrijven voor aanvallen op N-central RMM-servers, waarbij misbruik wordt gemaakt van twee kwetsbaarheden waarvoor beveiligingsupdates beschikbaar zijn. N-central i ... Read more

Published Date: Aug 19, 2026 (2 days, 16 hours ago)
  • TheCyberThrone
StormEncryptor Ransomware Dissection

TL;DRStorm-1175, a financially motivated ransomware actor tracked by Microsoft, has introduced a custom ransomware payload dubbed StormEncryptor, marking a notable evolution from its previous reliance ... Read more

Published Date: Aug 11, 2026 (1 week, 3 days ago)
  • The Hacker News
China-Linked Hackers Deploy New StormEncryptor Ransomware, Likely via N-central Flaw

Microsoft has disclosed that Storm-1175, a financially motivated threat actor linked to China, has deployed a previously undocumented ransomware strain called StormEncryptor. The use of StormEncryptor ... Read more

Published Date: Aug 10, 2026 (1 week, 4 days ago)
  • security.nl
Microsoft vermoedt dat criminelen ransomware verspreiden via N-Central-lek

Criminelen gebruiken vermoedelijk een beveiligingslek in N-Central van N-Able om organisaties met ransomware te infecteren, zo stelt Microsoft op X. Het gaat om een beveiligingslek aangeduid als CVE-2 ... Read more

Published Date: Aug 10, 2026 (1 week, 4 days ago)
  • The Hacker News
N-able Issues N-central Hotfix 2 as Attackers Reach Managed Systems and Persist

N-able has released a fresh round of hotfixes for N‑central as part of its investigation into ongoing exploitation of a recently disclosed security flaw in the Remote Monitoring and Management (RMM) p ... Read more

Published Date: Aug 08, 2026 (1 week, 6 days ago)
  • security.nl
N-able komt na aanvallen op N-central RMM-servers met tweede hotfix

N-able is na aanvallen op N-central RMM-servers met een tweede hotfix gekomen die klanten moeten installeren. Ook wordt aangeraden om te controleren of er geen verkeer naar CloudflareTunnel is. N-cent ... Read more

Published Date: Aug 07, 2026 (2 weeks ago)
  • TheCyberThrone
CISA Adds Four Vulnerabilities to KEV Catalog Aug 6 2026

Four Newly Added KEV Entries Reinforce the Growing Focus on Enterprise Management, AI, Middleware, and DevSecOps PlatformsThe U.S. Cybersecurity and Infrastructure  Security Agency (CISA) has expanded ... Read more

Published Date: Aug 06, 2026 (2 weeks, 1 day ago)
  • The Hacker News
CISA Flags Langflow RCE, Tomcat, and N-central Flaws as Actively Exploited

The U.S. Cybersecurity and Infrastructure Security Agency (CISA), on August 5, 2026, added three flaws to its Known Exploited Vulnerabilities (KEV) catalog, citing evidence of active exploitation in t ... Read more

Published Date: Aug 05, 2026 (2 weeks, 2 days ago)
  • The Hacker News
CISA Adds Exploited N-able N-central Flaw to KEV After Customer Compromises

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 ... Read more

Published Date: Aug 04, 2026 (2 weeks, 3 days ago)
  • The Hacker News
N-able Says Attackers Take Over N-central Servers After Initial Fix Proves Incomplete

N-able said attackers exploited an authentication bypass in N-central to gain remote administrative access and reach the customer systems managed through those servers. Its first fix was incomplete. C ... Read more

Published Date: Aug 03, 2026 (2 weeks, 4 days ago)
  • Huntress
Critical N-able N-central Vulnerability and Active Exploitation

Acknowledgments: Special thanks to Aaron Deal, Chris Bisnett, Aaron Bennett, Sharon Martin, Dave Kleinatland, James Northey, Josh Kiriakoff, Kamal Bennoune, and Michael Tigges for their contributions ... Read more

Published Date: Aug 03, 2026 (2 weeks, 4 days ago)

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2026-18556 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Aug. 05, 2026

    Action Type Old Value New Value
    Changed SSVC {'id': 'CVE-2026-18556', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'active'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-08-04T17:42:08.190557Z'} {'id': 'CVE-2026-18556', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'active'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-08-04T00:00:00+00:00'}
  • Modified Analysis by [email protected]

    Aug. 04, 2026

    Action Type Old Value New Value
    Added Reference Type CISA-ADP: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-18556 Types: US Government Resource
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Aug. 04, 2026

    Action Type Old Value New Value
    Added Reference https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-18556
    Changed SSVC {'id': 'CVE-2026-18556', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-08-04T13:10:59.591524Z'} {'id': 'CVE-2026-18556', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'active'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-08-04T17:42:08.190557Z'}
  • CVE CISA KEV Update by 9119a7d8-5eab-497f-8521-727c672e3725

    Aug. 04, 2026

    Action Type Old Value New Value
    Added Date Added 2026-08-04
    Added Due Date 2026-08-04
    Added Required Action 2026-08-04
    Added Vulnerability Name 2026-08-04
  • Initial Analysis by [email protected]

    Aug. 04, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
    Added CPE Configuration OR *cpe:2.3:a:n-able:n-central:*:*:*:*:*:*:*:* versions up to (including) 2026.1
    Added Reference Type CISA-ADP: https://www.n-able.com/blog/n-central-security-update-august-2-2026 Types: Vendor Advisory
    Added Reference Type N-able: https://uptime.n-able.com/ Types: Vendor Advisory
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Aug. 04, 2026

    Action Type Old Value New Value
    Added Reference https://www.n-able.com/blog/n-central-security-update-august-2-2026
    Changed SSVC {'id': 'CVE-2026-18556', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-08-03T16:48:46.194108Z'} {'id': 'CVE-2026-18556', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-08-04T13:10:59.591524Z'}
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Aug. 03, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-18556', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-08-03T16:48:46.194108Z'}
  • New CVE Received by a5532a13-c4dd-4202-bef1-e0b8f2f8d12b

    Aug. 01, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'N-able', 'product': 'N-central', 'versions': [{'status': 'affected', 'version': '0', 'versionType': 'custom', 'lessThanOrEqual': '2026.1'}], 'defaultStatus': 'unaffected'}]
    Added 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.
    Added CVSS V4.0 AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CWE CWE-288
    Added Reference https://uptime.n-able.com/
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CVSS
Vulnerability Scoring Details
Base CVSS Score: 8.2
Attack Vector
Attack Complexity
Attack Requirements
Privileges Required
User Interaction
VS Confidentiality
VS Integrity
VS Availability
SS Confidentiality
SS Integrity
SS Availability
Base CVSS Score: 7.4
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact