CVE-2020-37234 Overview
CVE-2020-37234 is a buffer overflow vulnerability [CWE-120] in Internet Download Manager (IDM) version 6.38.12. The flaw resides in the Scheduler component and is triggered when a local user pastes more than 5000 bytes into the Open the following file when done field. Oversized input overruns the underlying buffer and crashes the application, producing a denial of service condition. Exploitation requires local interaction with the IDM graphical interface, and the vulnerability does not yield remote code execution based on currently published research.
Critical Impact
Local attackers with access to the IDM Scheduler interface can crash Internet Download Manager 6.38.12, disrupting active and queued downloads.
Affected Products
- Internet Download Manager 6.38.12
- Internet Download Manager Scheduler component
- Windows installations running the affected IDM build
Discovery Timeline
- 2026-05-16 - CVE-2020-37234 published to the National Vulnerability Database
- 2026-05-18 - Last updated in NVD database
Technical Details for CVE-2020-37234
Vulnerability Analysis
The vulnerability is a classic stack-based buffer overflow in the Scheduler dialog of Internet Download Manager 6.38.12. The Open the following file when done text field accepts user-controlled input without enforcing a maximum length. When a string longer than 5000 bytes is pasted into the field, the application writes past the allocated buffer boundary and terminates with an access violation.
The public proof-of-concept on Exploit-DB (#49083) demonstrates the crash using a simple pasted payload. Current research describes the condition as a denial of service. There is no published evidence that the overflow leads to reliable code execution, and no known exploitation in the wild has been reported.
Root Cause
The root cause is missing input length validation on a GUI text field within the Scheduler. The application copies the user-supplied string into a fixed-size buffer without bounds checking, matching the [CWE-120] classic buffer copy without size check pattern.
Attack Vector
The attack vector is local. An attacker must have interactive access to the Windows desktop running IDM and be able to open the Scheduler dialog. The attacker pastes a string exceeding 5000 bytes into the target field and submits the form, causing IDM to crash. No authentication is required beyond local desktop access. Refer to the Exploit-DB #49083 entry and the VulnCheck advisory for the published proof-of-concept and technical write-up.
Detection Methods for CVE-2020-37234
Indicators of Compromise
- Unexpected crashes of IDMan.exe recorded in the Windows Application event log with access violation exception codes.
- Windows Error Reporting (WER) dump files for IDMan.exe containing oversized string data on the stack.
- Sudden termination of active IDM downloads coinciding with user activity in the Scheduler dialog.
Detection Strategies
- Monitor for IDMan.exe process termination events paired with Event ID 1000 (Application Error) referencing the IDM module.
- Inventory endpoints running Internet Download Manager 6.38.12 using software asset management or endpoint telemetry.
- Hunt for repeated IDM crash signatures across user workstations, which may indicate accidental triggering or local abuse.
Monitoring Recommendations
- Forward Windows Application and Reliability logs to a centralized log platform for crash correlation.
- Alert on clusters of IDMan.exe faults on the same host within a short time window.
- Track installed IDM versions during routine vulnerability scans and flag hosts still running 6.38.12.
How to Mitigate CVE-2020-37234
Immediate Actions Required
- Identify all endpoints running Internet Download Manager 6.38.12 and prioritize them for update.
- Upgrade Internet Download Manager to the latest release available from the official IDM download page.
- Restrict installation of IDM to users with a documented business need, reducing the attack surface on shared workstations.
Patch Information
No specific vendor advisory is referenced in the NVD record. Users should obtain the most recent version of Internet Download Manager directly from the Internet Download Manager website and verify that the installed build is later than 6.38.12. The VulnCheck advisory provides additional vendor context.
Workarounds
- Avoid pasting untrusted or unusually large content into the IDM Scheduler Open the following file when done field.
- Remove Internet Download Manager from systems where it is not required for business operations.
- Apply application allowlisting policies to limit who can launch IDMan.exe on shared or kiosk-style hosts.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
