CVE-2021-35302Network attack vector

Ticket data disclosure via faulty linked-ticket authorization

Published Jun 28, 2021 · Updated Aug 4, 2024

Incorrect access control in linked-ticket retrieval in Zammad 1.0.0 through 4.0.0 allows remote attackers to read restricted ticket data. Linked-ticket collection fails to enforce access controls for every gathered ticket, exposing information outside the requester’s permitted scope. No authentication or user interaction is required, and the consequence is limited to disclosure of ticket information.

CVSS severity5.3
Medium
EPSS probability1.20%
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 linked-ticket retrieval in Zammad 1.0.0 through 4.0.0 allows remote attackers to read restricted ticket data. Linked-ticket collection fails to enforce access controls for every gathered ticket, exposing information outside the requester’s permitted scope. No authentication or user interaction is required, and the consequence is limited to disclosure of ticket information.

The record

CVE
CVE-2021-35302
Published
Jun 28, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1213
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 28, 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

5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
5.0NIST NVDAV:N/AC:L/Au:N/C:P/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1213Data from Information Repositories

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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