CVE-2023-34108Public exploitNetwork attack vector

Security-control bypass via unescaped password return

Published Jun 7, 2023 · Updated Jan 6, 2025

Configuration injection in mailcow: dockerized 2023-05 and earlier allows remote authenticated users to alter Dovecot settings at login. The passwd-verify.lua script returns an accepted password in an unescaped password= string, so Dovecot parses text after a space as extra key-value fields. Any mailbox user able to change a password can reach the flaw; a demonstrated injected field disables mail encryption, and other fields can alter account-access controls.

CVSS severity8.8
High
EPSS probability0.98%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Configuration injection in mailcow: dockerized 2023-05 and earlier allows remote authenticated users to alter Dovecot settings at login. The passwd-verify.lua script returns an accepted password in an unescaped password= string, so Dovecot parses text after a space as extra key-value fields. Any mailbox user able to change a password can reach the flaw; a demonstrated injected field disables mail encryption, and other fields can alter account-access controls.

The record

CVE
CVE-2023-34108
Published
Jun 7, 2023
Updated
Jan 6, 2025
Vendor
mailcow
Product
mailcow: dockerized
Classifications
CWE-15, CWE-639, T1556
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 7, 2023CVE publishedPublication date reported by the CVE source.
  2. Jan 6, 2025Record 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=< 2023-05a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

mailcow · mailcow: dockerizedversion=< 2023-05a

Published CVSS scores

8.8GitHubCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-15External Control of System or Configuration Setting
CWE-639Authorization Bypass Through User-Controlled Key
T1556Modify Authentication Process

Public exploit references

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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