CVE-2023-23566Network attack vector

Mailbox access via protocol-specific two-step bypass

Published Jan 13, 2023 · Updated Apr 7, 2025

Authentication bypass in Axigen Mail Server 10.3.3.52 allows remote attackers to access a mailbox through IMAP or POP3 without a verification code. The server applies the one-time-code check to WebMail logins but accepts primary mailbox credentials over IMAP and POP3 without enforcing that second step. Exploitation requires valid mailbox credentials and an account with two-step verification enabled, exposing mailbox contents rather than bypassing the primary password.

CVSS severity9.8
Critical
EPSS probability0.95%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Authentication bypass in Axigen Mail Server 10.3.3.52 allows remote attackers to access a mailbox through IMAP or POP3 without a verification code. The server applies the one-time-code check to WebMail logins but accepts primary mailbox credentials over IMAP and POP3 without enforcing that second step. Exploitation requires valid mailbox credentials and an account with two-step verification enabled, exposing mailbox contents rather than bypassing the primary password.

The record

CVE
CVE-2023-23566
Published
Jan 13, 2023
Updated
Apr 7, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-276, T1078
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 13, 2023CVE publishedPublication date reported by the CVE source.
  2. Apr 7, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

9.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/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.

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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-276Incorrect Default Permissions
T1078Valid Accounts

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo