CVE-2025-30189Network attack vector

Authentication bypass via static authentication cache keys

Published Oct 31, 2025 · Updated Oct 31, 2025

Authentication cache corruption in OX Dovecot Pro core 2.4.0 allows remote attackers to access the first cached user's account. The auth passdb and userdb drivers use the obsolete %u expansion as an effectively static cache key, so one user's lookup overwrites entries for other users. Exploitation requires authentication caching with an affected oauth2, PAM, BSD auth, or passwd driver; subsequent logins are resolved as the first cached user.

CVSS severity7.4
High
EPSS probability0.54%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication cache corruption in OX Dovecot Pro core 2.4.0 allows remote attackers to access the first cached user's account. The auth passdb and userdb drivers use the obsolete %u expansion as an effectively static cache key, so one user's lookup overwrites entries for other users. Exploitation requires authentication caching with an affected oauth2, PAM, BSD auth, or passwd driver; subsequent logins are resolved as the first cached user.

The record

CVE
CVE-2025-30189
Published
Oct 31, 2025
Updated
Oct 31, 2025
Vendor
Open-Xchange GmbH
Product
OX Dovecot Pro
Classifications
CWE-1250
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 31, 2025CVE publishedPublication date reported by the CVE source.
  2. Oct 31, 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=0 <=2.4.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Open-Xchange GmbH · OX Dovecot Proversion=0 <=2.4.0

Published CVSS scores

7.4Open-Xchange GmbHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-1250Improper Preservation of Consistency Between Independent Representations of Shared State

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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