CVE-2019-9133 in KMPlayer
Summary
by MITRE
When processing subtitles format media file, KMPlayer version 2018.12.24.14 or lower doesn't check object size correctly, which leads to integer underflow then to memory out-of-bound read/write. An attacker can exploit this issue by enticing an unsuspecting user to open a malicious file.
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Analysis
by VulDB Data Team • 08/28/2023
The vulnerability identified as CVE-2019-9133 affects KMPlayer version 2018.12.24.14 and earlier, representing a critical security flaw in multimedia processing functionality. This issue manifests when the player handles subtitle format media files, specifically targeting the object size validation mechanisms within the software's parsing routines. The vulnerability stems from inadequate input validation that fails to properly verify the boundaries of parsed data structures, creating a dangerous condition that can be exploited by malicious actors.
The technical exploitation of this vulnerability relies on integer underflow conditions that occur during the processing of malformed subtitle files. When KMPlayer attempts to parse subtitle data, it fails to correctly validate the size parameters of objects within the media file structure, leading to arithmetic underflow scenarios. This underflow subsequently results in memory out-of-bounds read and write operations, where the application attempts to access memory locations beyond the allocated buffer boundaries. Such memory corruption can lead to arbitrary code execution, system instability, or information disclosure depending on the specific exploitation vector.
From an operational impact perspective, this vulnerability presents a significant risk to users who regularly process multimedia content, particularly in environments where untrusted media files might be encountered. The attack vector requires social engineering to entice users into opening maliciously crafted subtitle files, making it particularly dangerous in scenarios involving email attachments, file sharing platforms, or automated media processing systems. The vulnerability's classification aligns with CWE-190, Integer Overflow or Wraparound, and CWE-129, Improper Validation of Array Index, both of which are fundamental weaknesses in input validation and memory management.
Security researchers have identified this issue as a prime example of how multimedia processing applications can become attack surfaces for privilege escalation and remote code execution. The vulnerability's exploitation requires minimal user interaction, making it particularly concerning for enterprise environments where users may encounter untrusted media content. Organizations should consider implementing application whitelisting policies and restricting the execution of multimedia players on systems handling sensitive data. The ATT&CK framework categorizes this vulnerability under T1203, Exploitation for Client Execution, and T1059, Command and Scripting Interpreter, as it enables attackers to execute malicious code through compromised media processing applications. Mitigation strategies include immediate patching of affected KMPlayer versions, deployment of network segmentation to limit media file access, and implementation of automated threat detection systems that can identify suspicious file processing behaviors.