CyberSecBulletin
CVE-2023-23566NVD status: Modified

Axigen Mail Server: Incorrect Default Permissions

Published Updated By the CyberSecBulletin desk

CVE-2023-23566 is a critical-severity incorrect default permissions vulnerability in Axigen Mail Server from Axigen, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Axigen Mail Server versions: 10.3.3.52. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.03% chance of exploitation within 30 days, higher than 64% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of Axigen Mail Server you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on axigen.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
AxigenAxigen Mail Server10.3.3.52Not stated

Version data comes from NVD's product matching. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.19.8CriticalNVD
CVSS 3.19.8CriticalCISA (ADP)

Official description

A 2-Step Verification problem in Axigen 10.3.3.52 allows an attacker to access a mailbox by bypassing 2-Step Verification when they try to add an account to any third-party webmail service (or add an account to Outlook or Gmail, etc.) with IMAP or POP3 without any verification code.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Incorrect Default Permissions

During installation, installed file permissions are set to allow anyone to modify those files.

How developers prevent this class of flaw

  • The architecture needs to access and modification attributes for files to only those users who actually require those actions.
  • Compartmentalize the system to have safe areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.

More Incorrect Default Permissions vulnerabilities (CWE-276)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Axigen Mail Server

All Axigen Mail Server vulnerabilities

Recent Incorrect Default Permissions vulnerabilities

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