CVE-2021-42087Network attack vector

Application-secret disclosure via authenticated API response

Published Oct 7, 2021 · Updated Aug 4, 2024

Information disclosure in Zammad 1.0.x through 4.1.0 allows remote authenticated users with admin rights to read the application secret via the API. The affected API response returns the installation’s randomly generated application secret; the vendor has not disclosed the endpoint or serialization path. Administrator privileges and API authentication are required, and the reported consequence is secret disclosure without integrity or availability impact.

CVSS severity4.9
Medium
EPSS probability0.88%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in Zammad 1.0.x through 4.1.0 allows remote authenticated users with admin rights to read the application secret via the API. The affected API response returns the installation’s randomly generated application secret; the vendor has not disclosed the endpoint or serialization path. Administrator privileges and API authentication are required, and the reported consequence is secret disclosure without integrity or availability impact.

The record

CVE
CVE-2021-42087
Published
Oct 7, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1552
Attack vector
network
Privileges
admin

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 privilegesadmin

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

4.0NIST NVDAV:N/AC:L/Au:S/C:P/I:N/A:N
4.9NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1552Unsecured Credentials

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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