CVE-2021-35299

Email credential disclosure via connection-probe logging

Published Jun 28, 2021 · Updated Aug 4, 2024

Sensitive data exposure in Zammad 1.0.x through 4.0.0 allows attackers with log-file access to read valid email credentials. The full inbound-and-outbound email connection probe writes successfully validated credentials into the Zammad application log. The disclosure is limited to credentials from successful full probes and requires the attacker to obtain access to that log file.

CVSS severity7.5
High
EPSS probability1.12%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Sensitive data exposure in Zammad 1.0.x through 4.0.0 allows attackers with log-file access to read valid email credentials. The full inbound-and-outbound email connection probe writes successfully validated credentials into the Zammad application log. The disclosure is limited to credentials from successful full probes and requires the attacker to obtain access to that log file.

The record

CVE
CVE-2021-35299
Published
Jun 28, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-532, T1552.001
Attack vector
Unavailable
Privileges
Unavailable

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 vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.0NIST NVDAV:N/AC:L/Au:N/C:P/I:N/A:N
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/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.

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)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-532Insertion of Sensitive Information into Log File
T1552.001Unsecured Credentials: Credentials In Files

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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