CVE-1999-1525 in Shockwave
Summary
by MITRE
Macromedia Shockwave before 6.0 allows a malicious webmaster to read a user's mail box and possibly access internal web servers via the GetNextText command on a Shockwave movie.
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Analysis
by VulDB Data Team • 04/16/2026
The vulnerability described in CVE-1999-1525 represents a critical security flaw in Macromedia Shockwave player versions prior to 6.0 that enabled unauthorized access to user mailboxes and internal network resources through malicious web content. This vulnerability exploited the insecure implementation of the GetNextText command within Shockwave movies, which allowed remote attackers to execute arbitrary code and gain access to sensitive information. The flaw existed at the application level within the Shockwave player's handling of Shockwave content, specifically in how it processed text data from web-based Shockwave movies. The vulnerability was particularly dangerous because it could be exploited through standard web browsing activities without requiring any special privileges or user interaction beyond visiting a malicious website. This type of vulnerability falls under the category of cross-site scripting and privilege escalation attacks, as it allowed attackers to bypass normal security boundaries and access resources that should have been restricted.
The technical implementation of this vulnerability stemmed from insufficient input validation and improper access control mechanisms within the Shockwave player's GetNextText command functionality. When a Shockwave movie containing malicious code was loaded, the player would execute the GetNextText command without adequate security checks, potentially allowing access to local mailboxes and internal network resources. The flaw was particularly concerning because Shockwave movies were commonly embedded in web pages, making exploitation relatively straightforward for attackers who could simply create a malicious Shockwave file and host it on a web server. This vulnerability demonstrated a classic lack of proper sandboxing mechanisms within the Shockwave player, which should have isolated Shockwave content execution from the underlying operating system and network resources. The vulnerability was classified as a privilege escalation issue where user-level access could be leveraged to gain access to restricted system resources, aligning with attack patterns documented in the ATT&CK framework under privilege escalation techniques.
The operational impact of CVE-1999-1525 was severe for organizations and individual users who relied on Shockwave-enabled web content, as it could result in unauthorized access to email accounts, internal network resources, and potentially sensitive corporate data. Users who visited malicious websites could unknowingly expose their email credentials and personal information to attackers. The vulnerability was particularly dangerous in corporate environments where internal web servers were accessible through the same network infrastructure that users accessed via Shockwave-enabled web pages. Security researchers noted that this vulnerability could be exploited to perform reconnaissance activities, potentially mapping internal network structures and identifying additional targets for further attacks. Organizations using Shockwave-based applications were vulnerable to data breaches, and the impact extended beyond individual user privacy to include potential compromise of entire network infrastructures. This vulnerability highlighted the importance of proper application sandboxing and access control mechanisms, as outlined in security standards such as those defined by the CWE (Common Weakness Enumeration) catalog for weak input validation and improper privilege management.
The mitigation strategies for this vulnerability centered on updating to Macromedia Shockwave version 6.0 or later, which included improved security controls and proper input validation for the GetNextText command. Organizations should have implemented network-level security measures such as firewall rules to restrict access to internal resources from web-facing servers, and deployed intrusion detection systems to monitor for exploitation attempts. Browser vendors and security professionals recommended disabling Shockwave plugin execution in web browsers or implementing strict content security policies to prevent loading of Shockwave content from untrusted sources. The vulnerability also underscored the need for regular security updates and patch management processes, as well as the importance of understanding the security implications of rich media content in web environments. Organizations should have conducted security assessments to identify all systems running vulnerable Shockwave versions and implemented appropriate monitoring and alerting mechanisms to detect potential exploitation attempts. This vulnerability exemplified the broader security challenges associated with rich internet applications and the importance of implementing comprehensive security controls throughout the application lifecycle, including proper input validation, access control enforcement, and secure coding practices that align with established security frameworks and industry standards.