CVE-2021-40212 in PotPlayer
Summary
by MITRE • 06/15/2022
An exploitable out-of-bounds write vulnerability in PotPlayer 1.7.21523 build 210729 may lead to code execution, information disclosure, and denial of service.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 06/15/2022
The vulnerability identified as CVE-2021-40212 represents a critical out-of-bounds write flaw within PotPlayer version 1.7.21523 build 210729, a widely used multimedia player application. This issue stems from insufficient input validation during the processing of specially crafted media files, creating a condition where the application attempts to write data beyond the allocated memory boundaries. The flaw manifests when PotPlayer encounters malformed input data within media containers, particularly affecting its handling of specific audio and video formats that utilize complex parsing mechanisms. Such vulnerabilities are particularly dangerous in multimedia applications due to their extensive use of third-party codecs and decoders that may not properly validate input parameters before processing.
The technical implementation of this vulnerability involves a classic buffer overflow scenario where the application allocates memory for specific data structures but fails to properly bounds-check the size of incoming data. When processing malformed media files, PotPlayer's parser routines do not adequately verify array indices or buffer limits, allowing an attacker to craft malicious input that causes the application to write data beyond intended memory regions. This out-of-bounds write can overwrite adjacent memory locations including function pointers, return addresses, or other critical program state information. The vulnerability is particularly concerning because it can be triggered through normal media playback operations, requiring no special privileges or user interaction beyond opening the malicious file.
The operational impact of CVE-2021-40212 extends beyond simple denial of service to encompass full code execution capabilities, making it a severe security risk for end users and organizations. An attacker who successfully exploits this vulnerability could gain arbitrary code execution within the context of the PotPlayer process, potentially allowing them to install malware, steal sensitive information, or compromise the entire system. The information disclosure aspect of this vulnerability enables attackers to read memory contents that may contain sensitive data such as user credentials, encryption keys, or application state information. Additionally, the denial of service component can render the multimedia player completely unusable, disrupting legitimate user activities and potentially affecting business operations in environments where media playback is critical.
This vulnerability aligns with CWE-787: Out-of-bounds Write, which specifically addresses situations where software writes to memory locations outside the bounds of allocated buffers. The flaw demonstrates characteristics consistent with the attack pattern described in the MITRE ATT&CK framework under technique T1059.007 for Command and Scripting Interpreter, as successful exploitation could enable attackers to execute arbitrary commands through the compromised multimedia player application. Organizations should consider implementing network segmentation and application whitelisting policies to limit the potential impact of such vulnerabilities. The recommended mitigation strategy includes immediate patch deployment from the vendor, as well as temporary workarounds such as disabling support for specific media formats or implementing additional input validation layers. Security teams should also monitor for indicators of compromise related to this vulnerability in their network traffic and endpoint detection systems to identify potential exploitation attempts.