CVE-2024-39927 Overview
CVE-2024-39927 is an out-of-bounds write vulnerability [CWE-787] affecting Ricoh multifunction printers (MFPs) and printers. A remote attacker can send a specially crafted request to a vulnerable device to trigger the flaw. Successful exploitation can cause a denial-of-service (DoS) condition and may destroy user data stored on the device.
The issue is exploitable over the network without authentication or user interaction. The vulnerability carries a CVSS 3.1 base score of 8.2 and is categorized as high severity. The EPSS score is 0.576% with a percentile of 42.97 as of 2026-06-23.
Critical Impact
A remote, unauthenticated attacker can crash affected Ricoh MFPs and printers or corrupt user data by sending a crafted network request.
Affected Products
- Ricoh multifunction printers (MFPs) listed in advisory ricoh-2024-000008
- Ricoh printers listed in advisory ricoh-2024-000008
- Refer to the Ricoh Vulnerability Advisory for the full model and firmware list
Discovery Timeline
- 2024-07-10 - CVE-2024-39927 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2024-39927
Vulnerability Analysis
The vulnerability is an out-of-bounds write condition in network-facing service code on Ricoh MFPs and printers. When the device processes a specially crafted request, it writes data beyond the bounds of an allocated buffer. The result is memory corruption that can crash the printing service or destroy user data persisted on the device.
Because MFPs typically expose printing, scanning, and management services on the corporate LAN, the attack surface is broad. Affected services accept input from the network and parse structured request data without enforcing correct length or boundary checks. The vulnerability does not require valid credentials or any user interaction on the device.
Root Cause
The root cause is improper validation of the size or offset of attacker-controlled data before it is copied into a fixed-size buffer. This is a classic [CWE-787] out-of-bounds write pattern. Ricoh's advisory ricoh-2024-000008 documents the affected components but does not publish the vulnerable function names. See the JVN Security Advisory for additional technical context.
Attack Vector
The attack vector is Network (AV:N) with low complexity and no privileges or user interaction required. An attacker on the same network as a vulnerable device, or able to reach it across a routed segment, can send a crafted request to the listening service. The integrity impact is limited (I:L) because the corruption can destroy stored user data, while the availability impact is high (A:H) because the device can be taken out of service. The vulnerability does not disclose information (C:N).
No public proof-of-concept exploit is available, and the issue is not listed in the CISA Known Exploited Vulnerabilities catalog.
Detection Methods for CVE-2024-39927
Indicators of Compromise
- Unexpected reboots, crashes, or service restarts on Ricoh MFPs and printers
- Loss or corruption of stored documents, address books, or job logs on the device
- Failed print or scan operations correlated with anomalous inbound traffic to printer management ports
- Inbound connections to printer services from unusual internal hosts or external sources
Detection Strategies
- Monitor printer SNMP, syslog, and device event logs for repeated service restarts and memory faults
- Inspect network flows for malformed or oversized requests directed at Ricoh printer service ports
- Correlate device-side errors with packet captures at network choke points serving the print VLAN
- Apply intrusion detection signatures published by Ricoh or JVN once available for ricoh-2024-000008
Monitoring Recommendations
- Forward printer syslog and SNMP traps to a centralized SIEM or data lake for correlation
- Baseline normal traffic patterns to MFPs and alert on deviations such as new source IPs or protocol anomalies
- Track firmware versions across the fleet to identify devices still exposed to CVE-2024-39927
How to Mitigate CVE-2024-39927
Immediate Actions Required
- Identify all Ricoh MFPs and printers in the environment and cross-reference firmware against ricoh-2024-000008
- Apply the vendor-provided firmware update on every affected device as soon as it is available
- Restrict network reachability to printer management and printing services to authorized print servers and administrative subnets
- Disable unused network protocols and services on each device to reduce the exposed attack surface
Patch Information
Ricoh has published firmware updates and mitigation guidance in the advisory ricoh-2024-000008. Administrators should consult the Ricoh Vulnerability Advisory and the JVN Security Advisory for model-specific firmware versions and update instructions.
Workarounds
- Place MFPs and printers on a dedicated VLAN with ACLs that allow only required print and management traffic
- Block printer service ports at the perimeter and at internal firewalls separating untrusted segments
- Require devices to sit behind a print server rather than accepting direct client connections where feasible
- Disable remote management interfaces on devices that do not need them until firmware updates are applied
# Example ACL restricting printer access to an authorized print server subnet
# Replace 10.10.20.0/24 with the print server subnet and 10.10.50.10 with the printer IP
access-list PRINTER_IN permit tcp 10.10.20.0/24 host 10.10.50.10 eq 9100
access-list PRINTER_IN permit tcp 10.10.20.0/24 host 10.10.50.10 eq 631
access-list PRINTER_IN permit udp 10.10.20.0/24 host 10.10.50.10 eq 161
access-list PRINTER_IN deny ip any host 10.10.50.10 log
access-list PRINTER_IN permit ip any any
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
