CVE-2021-40859Public exploitNetwork attack vector

Administrative takeover via derivable backdoor passwords

Published Dec 7, 2021 · Updated Aug 4, 2024

Authentication bypass in Auerswald COMpact 5500R 7.8A and 8.0B allows remote attackers to obtain full administrative access. The web login accepts undocumented Schandelah and Admin passwords derived by MD5-hashing the device serial number, current date, and language. Unauthenticated /about_state responses expose every input needed to calculate the passwords, so network access to the management interface enables complete device compromise.

CVSS severity9.8
Critical
EPSS probability71.98%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication bypass in Auerswald COMpact 5500R 7.8A and 8.0B allows remote attackers to obtain full administrative access. The web login accepts undocumented Schandelah and Admin passwords derived by MD5-hashing the device serial number, current date, and language. Unauthenticated /about_state responses expose every input needed to calculate the passwords, so network access to the management interface enables complete device compromise.

The record

CVE
CVE-2021-40859
Published
Dec 7, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1078.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 7, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record 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

9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
10.0NIST NVDAV:N/AC:L/Au:N/C:C/I:C/A:C

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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

T1078.001Valid Accounts: Default 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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