CVE-2026-63206Network attack vectorHinoki check available

Ticket-view activity disclosure via shortened image URL

Published Sep 25, 2026 · Updated Sep 25, 2026

Improper input validation in Zammad before 7.1.2 allows remote attackers to disclose ticket-view activity via a crafted image URL. The HTML sanitizer recognizes conventional scheme delimiters but fails to classify forms such as http:host/path as remote, although browsers resolve them like http://host/path. Exploitation requires a recipient to open the crafted ticket or email; the browser then contacts the attacker's server without showing the remote-content warning.

CVSS severity5.3
Medium
EPSS probability0.28%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
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Summary

What happened

Improper input validation in Zammad before 7.1.2 allows remote attackers to disclose ticket-view activity via a crafted image URL. The HTML sanitizer recognizes conventional scheme delimiters but fails to classify forms such as http:host/path as remote, although browsers resolve them like http://host/path. Exploitation requires a recipient to open the crafted ticket or email; the browser then contacts the attacker's server without showing the remote-content warning.

The record

CVE
CVE-2026-63206
Published
Sep 25, 2026
Updated
Sep 25, 2026
Vendor
Zammad GmbH
Product
Zammad
Classifications
CWE-20, CWE-184
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 25, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 7.1.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Zammad GmbH · Zammadversion=< 7.1.2

Published CVSS scores

5.3Zammad GitHub Security AdvisoryCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA: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.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
CWE-184Incomplete List of Disallowed Inputs

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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