CVE-2026-63208Network attack vectorHinoki check available

OAuth token disclosure via incomplete JWT log masking

Published Sep 25, 2026 · Updated Sep 25, 2026

Information disclosure in Zammad before 7.1.2 allows remote authenticated users to read partial Microsoft Graph OAuth tokens from error logs. HttpLog's bearer-token regular expression masks only the first dot-delimited JWT segment and leaves later segments readable in stored request or response headers. Access requires a Zammad administrator with Microsoft Graph channel permissions, and the exposed segments reveal token claims and aid token reconstruction while valid.

CVSS severity5.1
Medium
EPSS probability0.31%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Information disclosure in Zammad before 7.1.2 allows remote authenticated users to read partial Microsoft Graph OAuth tokens from error logs. HttpLog's bearer-token regular expression masks only the first dot-delimited JWT segment and leaves later segments readable in stored request or response headers. Access requires a Zammad administrator with Microsoft Graph channel permissions, and the exposed segments reveal token claims and aid token reconstruction while valid.

The record

CVE
CVE-2026-63208
Published
Sep 25, 2026
Updated
Sep 25, 2026
Vendor
Zammad GmbH
Product
Zammad
Classifications
CWE-532, CWE-116, T1552
Attack vector
network
Privileges
admin

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 privilegesadmin

What is affected?

Zammad GmbH · Zammadversion=< 7.1.2

Published CVSS scores

5.1GitHub CNACVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:N/VA:N/SC:L/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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-532Insertion of Sensitive Information into Log File
CWE-116Improper Encoding or Escaping of Output
T1552Unsecured Credentials

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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