CVE-2026-36539Public exploitNetwork attack vector

Unauthenticated configuration disclosure via exposed CGI endpoint

Published May 27, 2026 · Updated May 27, 2026

Information disclosure in Netis AC1200 Router NC21 4.0.1.4296 allows remote attackers on the LAN to read router secrets. The unauthenticated /cgi-bin/skk_get.cgi handler serializes the complete running configuration to JSON and returns Base64-encoded secrets without an access check. LAN reachability alone exposes administrator, Wi-Fi, PPPoE, and DDNS credentials plus connected-device details; no configuration change is required.

CVSS severity7.3
High
EPSS probability0.36%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in Netis AC1200 Router NC21 4.0.1.4296 allows remote attackers on the LAN to read router secrets. The unauthenticated /cgi-bin/skk_get.cgi handler serializes the complete running configuration to JSON and returns Base64-encoded secrets without an access check. LAN reachability alone exposes administrator, Wi-Fi, PPPoE, and DDNS credentials plus connected-device details; no configuration change is required.

The record

CVE
CVE-2026-36539
Published
May 27, 2026
Updated
May 27, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-200
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 27, 2026CVE publishedPublication date reported by the CVE source.
  2. May 27, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.3CISA ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-200Exposure of Sensitive Information to an Unauthorized Actor

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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