CVE-2021-31762Public exploitNetwork attack vector

Remote command execution via missing referer checks

Published Apr 25, 2021 · Updated Aug 3, 2024

Cross-site request forgery in Webmin 1.973 allows remote attackers to create a privileged user through a malicious link. The acl/save_user.cgi endpoint accepts a cross-origin POST under an authenticated administrator's session when setup.pl leaves unknown-referer checking disabled. The administrator must follow the link while signed in; the new privileged account can then use Running Processes to execute commands on the server.

CVSS severity8.8
High
EPSS probability8.78%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site request forgery in Webmin 1.973 allows remote attackers to create a privileged user through a malicious link. The acl/save_user.cgi endpoint accepts a cross-origin POST under an authenticated administrator's session when setup.pl leaves unknown-referer checking disabled. The administrator must follow the link while signed in; the new privileged account can then use Running Processes to execute commands on the server.

The record

CVE
CVE-2021-31762
Published
Apr 25, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-352, T1136, T1204.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 25, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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

6.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:P
8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/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.

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

CWE-352Cross-Site Request Forgery (CSRF)
T1136Create Account
T1204.001User Execution: Malicious Link

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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