Vulnerabilities in the CA certificate download and the diagnostic log functionality on B/W small multifunction and single-function printers
January 29, 2026
Konica Minolta, Inc.
Dear Customers,
We deeply appreciate your constant patronage to Konica Minolta products.
Two security vulnerabilities have been newly identified in the indicated models.
This advisory provides an overview of the issue and guidance on how to resolve them.
Please note that, at the time of publication, there have been no confirmed security incidents globally resulting from the exploitation of these vulnerabilities.
Overview of the vulnerabilities
| CVE-ID | CVSS Assessment | Base Score | Vulnerabilities description |
| CVE-2025-53869 | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N | 6.3 | The set of root certificates used by the product may be replaced with a set of arbitrary certificates by a man-in-the-middle attack. (CWE-295: Improper certificate validation) |
| CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N | 3.7 | ||
| CVE-2025-55704 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N | 6.9 | An attacker may obtain the logs of the affected product and obtain sensitive information within the logs. (CWE-912: Hidden Functionality) |
| CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N | 5.3 |
Affected Models
| Product name | Program name | Affected version | Fixed version |
| bizhub 5021i | Firmware | 1.02 | 1.04 |
| bizhub 5001i | Firmware | 1.03 | 1.05 |
| bizhub 4221i | Firmware | 1.02 | 1.04 |
| bizhub 4201i | Firmware | 1.02 | 1.04 |
| bizhub 5020i | Main-Firmware | U2412241059 （Ver S）or earlier | U2505151336 (Ver T) or later |
| Sub-Firmware | 1.15 or earlier | 1.16 or later | |
| bizhub 5000i | Main-Firmware | 1.33 or earlier | 1.34 or later |
| Sub-Firmware | 1.15 or earlier | 1.16 or later | |
| bizhub 4020i | Main-Firmware | U2412241059 （Ver S）or earlier | U2505151336 (Ver T) or later |
| Sub-Firmware | 1.15 or earlier | 1.16 or later | |
| bizhub 4000i | Main-Firmware | 1.29 or earlier | 1.30 or later |
| Sub-Firmware | 1.15 or earlier | 1.16 or later |
Remediation
Download the Firmware Update Tool from Drivers & Downloads and upgrade the firmware of your device.
General Security Recommendations
To ensure a secure operating posture for your multifunction devices, and to reduce exposure to the vulnerability described in this advisory, Konica Minolta strongly recommends applying the following configuration best practices:
- Avoid Direct Internet Exposure
Place devices behind firewalls and use private IP addressing.
- Change Default Passwords
Change default credentials and implement strong passwords for administrative and network functions.
- Use Strong Passwords for Services
Ensure strong credentials are configured for SMTP, LDAP, SMB, WebDAV, and any other integrated services.
- Disable Unused Services
Turn off unused ports or protocols to reduce attack surface.
- Use Secure Protocols
Configure devices to use encrypted communications (e.g., HTTPS, LDAPS, IPPS) where supported.
- Monitor Device Activity
Regularly review device logs and network traffic for suspicious behaviour.
- Enable Authentication Where Available
Use built-in user authentication features to prevent unauthorised access to device functions.
For comprehensive information on secure configuration, please refer to our Product Security web site.
Enhancing the Security of Products and Services
Konica Minolta considers the security of its products and services to be an important responsibility and will continue to actively respond to incidents and vulnerabilities.
Related Information
JVNVU#92878805
Contact
Should you require further clarification or assistance with implementing the recommended measures or applying the relevant firmware update, please contact your authorised Konica Minolta service representative.