CVE-2025-14236 Overview
CVE-2025-14236 is a buffer overflow vulnerability affecting Canon Small Office Multifunction Printers and Laser Printers. The vulnerability exists in the Address Book attribute tag processing functionality, which fails to properly validate input boundaries when handling attribute tags. An attacker on the same network segment can exploit this flaw to cause the affected device to become unresponsive or achieve arbitrary code execution on the vulnerable printer.
Critical Impact
Network-adjacent attackers can exploit this buffer overflow to execute arbitrary code or cause denial of service on Canon multifunction printers and laser printers running vulnerable firmware versions.
Affected Products
- Satera LBP670C Series/Satera MF750C Series firmware v06.02 and earlier (Japan)
- Color imageCLASS LBP630C/Color imageCLASS MF650C Series/imageCLASS LBP230 Series/imageCLASS X LBP1238 II/imageCLASS MF450 Series/imageCLASS X MF1238 II/imageCLASS X MF1643i II/imageCLASS X MF1643iF II firmware v06.02 and earlier (US)
- i-SENSYS LBP630C Series/i-SENSYS MF650C Series/i-SENSYS LBP230 Series/1238P II/1238Pr II/i-SENSYS MF450 Series/i-SENSYS MF550 Series/1238i II/1238iF II/imageRUNNER 1643i II/imageRUNNER 1643iF II firmware v06.02 and earlier (Europe)
Discovery Timeline
- January 16, 2026 - CVE-2025-14236 published to NVD
- January 16, 2026 - Last updated in NVD database
Technical Details for CVE-2025-14236
Vulnerability Analysis
This vulnerability is classified as CWE-787 (Out-of-bounds Write), a critical memory corruption issue that occurs when the printer's firmware writes data beyond the boundaries of the allocated memory buffer during Address Book attribute tag processing. The flaw resides in the network-accessible Address Book functionality of affected Canon printer models.
When processing specially crafted Address Book attribute tags sent over the network, the firmware fails to properly validate the length or format of the input data. This allows an attacker to overflow the buffer and overwrite adjacent memory, potentially corrupting control flow data structures and enabling arbitrary code execution on the embedded printer system.
The network attack vector means any threat actor with access to the same network segment as the vulnerable printer can attempt exploitation without requiring authentication or user interaction. Given the prevalence of multifunction printers in corporate environments and their often-overlooked security posture, this vulnerability presents significant risk for lateral movement and persistence within enterprise networks.
Root Cause
The root cause is improper input validation in the Address Book attribute tag parsing routine. The firmware does not adequately check the size of incoming data against the allocated buffer capacity before writing the data, resulting in an out-of-bounds write condition. This type of vulnerability typically stems from unsafe memory handling functions that do not enforce bounds checking.
Attack Vector
The attack is network-based and requires the attacker to be on the same network segment as the target printer. The exploitation flow involves:
- The attacker identifies a vulnerable Canon printer on the local network segment
- The attacker crafts a malicious network request containing oversized or malformed Address Book attribute tag data
- The malicious request is sent to the printer's network service handling Address Book operations
- The vulnerable parsing routine attempts to process the data without proper bounds checking
- The buffer overflow occurs, allowing the attacker to overwrite adjacent memory
- Depending on the specific memory layout, this can lead to denial of service (device becomes unresponsive) or arbitrary code execution
The vulnerability can be exploited remotely by any attacker with network adjacency, requiring no authentication credentials or user interaction on the target device.
Detection Methods for CVE-2025-14236
Indicators of Compromise
- Unexpected printer reboots or devices becoming unresponsive without explanation
- Unusual network traffic patterns targeting printer IP addresses on Address Book-related ports
- Anomalous firmware modifications or configuration changes on affected Canon devices
- Multiple failed or unusual requests to printer management interfaces from internal hosts
Detection Strategies
- Monitor network traffic for anomalous or oversized packets directed at Canon printer management interfaces
- Implement intrusion detection rules to identify potential buffer overflow exploitation attempts against printer devices
- Review printer event logs for crash events, unexpected restarts, or error conditions indicating memory corruption
- Conduct periodic firmware version audits to identify devices running vulnerable firmware v06.02 or earlier
Monitoring Recommendations
- Enable logging on network segmentation devices to track traffic to and from printer VLANs
- Deploy network-based anomaly detection to identify unusual communication patterns with printer endpoints
- Establish baseline behavior for printer network activity and alert on deviations
- Monitor for signs of lateral movement originating from printer IP addresses
How to Mitigate CVE-2025-14236
Immediate Actions Required
- Identify all Canon multifunction printers and laser printers in your environment running firmware v06.02 or earlier
- Isolate vulnerable printers on dedicated network segments with restricted access until patched
- Apply firmware updates as soon as they become available from Canon
- Review and restrict network access to printer management interfaces using firewall rules or ACLs
Patch Information
Canon has acknowledged this vulnerability and provided remediation guidance. Organizations should obtain the latest firmware updates through official Canon support channels. Refer to the Canon PSIRT Advisory CP2026-001 for specific patch details and firmware download instructions.
Additional vendor resources:
Workarounds
- Segment printers on isolated VLANs with strict firewall rules limiting access to only necessary hosts and ports
- Disable or restrict network access to Address Book functionality if not required for business operations
- Implement network access control to prevent unauthorized devices from communicating with printer management interfaces
- Consider disabling remote management features until firmware updates can be applied
# Example network segmentation firewall rule (adjust for your environment)
# Block external access to printer management ports
iptables -A INPUT -s ! 10.0.1.0/24 -d 10.0.2.0/24 -p tcp --dport 9100 -j DROP
iptables -A INPUT -s ! 10.0.1.0/24 -d 10.0.2.0/24 -p tcp --dport 631 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
