CVE-2008-4984 in scratchbox2
Summary
by MITRE
scratchbox2 1.99.0.24 allows local users to overwrite arbitrary files via a symlink attack on (a) /tmp/dpkg.#####.tmp, (b) /tmp/missing_deps.#####, and (c) /tmp/sb2-pkg-chk.$tstamp.##### temporary files, related to the (1) dpkg-checkbuilddeps and (2) sb2-check-pkg-mappings scripts.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 10/14/2018
The vulnerability identified as CVE-2008-4984 affects scratchbox2 version 1.99.0.24 and represents a significant local privilege escalation vector through insecure temporary file handling. This flaw enables local attackers to overwrite arbitrary files on the system by exploiting symbolic link attacks against three specific temporary files created during package management operations. The vulnerability stems from the improper creation of temporary files in the /tmp directory without adequate security measures to prevent symlink-based attacks, which falls under the CWE-377 vulnerability category for insecure temporary file creation and the CWE-378 weakness for insecure temporary file creation with predictable names.
The technical implementation of this vulnerability occurs within the dpkg-checkbuilddeps and sb2-check-pkg-mappings scripts that are part of the scratchbox2 development environment. These scripts create temporary files with predictable naming patterns using format strings that include process identifiers and timestamps, making them susceptible to symlink attacks. When the scripts execute, they create temporary files such as /tmp/dpkg.#####.tmp, /tmp/missing_deps.#####, and /tmp/sb2-pkg-chk.$tstamp.##### where the hash symbols represent predictable numeric sequences. Attackers can establish symbolic links with these exact names in the /tmp directory before the scripts execute, causing the scripts to write data to attacker-controlled locations instead of the intended temporary files.
The operational impact of this vulnerability extends beyond simple file overwriting capabilities, as it provides a mechanism for local privilege escalation and arbitrary code execution. An attacker who gains access to a system with scratchbox2 installed can leverage this vulnerability to overwrite critical system files, configuration files, or even binaries with malicious content. This creates potential for persistent backdoors, privilege escalation to root level, and complete system compromise. The vulnerability is particularly concerning in multi-user environments where users may not have elevated privileges but can still exploit the temporary file creation flaw to gain unauthorized access to system resources.
Security mitigations for this vulnerability should focus on implementing proper temporary file creation practices that prevent symbolic link attacks. The recommended approaches include using secure temporary file creation functions that check for symbolic links, implementing atomic file creation using file descriptor operations, and ensuring that temporary files are created with proper permissions and ownership. Organizations should also consider implementing the ATT&CK technique T1059.007 for command and scripting interpreter usage, as attackers may leverage this vulnerability to establish persistent access through compromised temporary files. Additionally, the principle of least privilege should be enforced by ensuring that scratchbox2 processes run with minimal required permissions and that temporary files are created in secure directories with restricted access permissions rather than in the world-accessible /tmp directory. The vulnerability demonstrates the critical importance of secure file handling practices and proper sandboxing techniques in development environments to prevent local privilege escalation attacks that can compromise entire system security postures.