CVE-2021-42086Network attack vector

Agent-to-administrator escalation via crafted account request

Published Oct 7, 2021 · Updated Aug 4, 2024

Privilege escalation in Zammad 4.1.0 and earlier allows remote authenticated users with Agent accounts to gain admin access. Zammad has not published the affected endpoint or the authorization error that lets a crafted request modify another agent account. Agent-level access is required, and the modified account can then be used to log in with administrative privileges.

CVSS severity8.8
High
EPSS probability1.11%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Privilege escalation in Zammad 4.1.0 and earlier allows remote authenticated users with Agent accounts to gain admin access. Zammad has not published the affected endpoint or the authorization error that lets a crafted request modify another agent account. Agent-level access is required, and the modified account can then be used to log in with administrative privileges.

The record

CVE
CVE-2021-42086
Published
Oct 7, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1068
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 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 privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
6.5NIST NVDAV:N/AC:L/Au:S/C:P/I:P/A:P

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1068Exploitation for Privilege Escalation

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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