CVE-2026-38577Public exploitNetwork attack vector

Root access via static Admin account credentials

Published Aug 31, 2026 · Updated Sep 1, 2026

Hardcoded credentials in Tenda HG21 4.0.0-260302 allow remote attackers to authenticate as the device's root administrator. The firmware's /etc/passwd file contains an admin entry with a SHA256crypt hash for a static password shared across devices. Network access to an exposed management service and knowledge of the embedded credential are sufficient to bypass the customer-set web password and obtain UID 0 control.

CVSS severity9.8
Critical
EPSS probability0.33%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Hardcoded credentials in Tenda HG21 4.0.0-260302 allow remote attackers to authenticate as the device's root administrator. The firmware's /etc/passwd file contains an admin entry with a SHA256crypt hash for a static password shared across devices. Network access to an exposed management service and knowledge of the embedded credential are sufficient to bypass the customer-set web password and obtain UID 0 control.

The record

CVE
CVE-2026-38577
Published
Aug 31, 2026
Updated
Sep 1, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-798, T1078.003
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 31, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 1, 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

9.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-798Use of Hard-coded Credentials
T1078.003Local Accounts

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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