CVE-2020-11891Network attack vector

Unauthorized usergroup editing via incorrect ACL checks

Published Apr 21, 2020 · Updated Aug 4, 2024

Incorrect access control in Joomla! CMS 3.8.8 through 3.9.16 allows remote attackers to edit usergroups through com_users. The access-level editing path in com_users performs incorrect ACL checks before accepting usergroup changes; Joomla! has not disclosed the exact missing or misapplied check. Network access without authentication is sufficient, and successful exploitation changes authorization data rather than disclosing information or interrupting service.

CVSS severity5.3
Medium
EPSS probability0.80%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Incorrect access control in Joomla! CMS 3.8.8 through 3.9.16 allows remote attackers to edit usergroups through com_users. The access-level editing path in com_users performs incorrect ACL checks before accepting usergroup changes; Joomla! has not disclosed the exact missing or misapplied check. Network access without authentication is sufficient, and successful exploitation changes authorization data rather than disclosing information or interrupting service.

The record

CVE
CVE-2020-11891
Published
Apr 21, 2020
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1098
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 21, 2020CVE 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

5.0NIST NVDAV:N/AC:L/Au:N/C:N/I:P/A:N
5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

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 exploitUnconfirmed

Weakness, pattern, technique

T1098Account Manipulation

Public exploit references

No public exploit references are available in this record.

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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