Executive brief
A vulnerability exists in the zgv image viewer component of the svgalib library, which is used for graphics display on Linux systems. A local user can exploit this flaw to gain unauthorized control over the system by running malicious code. This could lead to a full system compromise or unauthorized access to sensitive data stored on the machine.
Technical details
A stack-based buffer overflow exists in the zgv utility within svgalib versions 1.2.10 and earlier. The vulnerability is triggered when the application processes an excessively long HOME environment variable without proper bounds checking. Because zgv often runs with elevated privileges (such as setuid root) to access graphics hardware, a local attacker can exploit this overflow to overwrite the instruction pointer and execute arbitrary code with the privileges of the zgv process. This is a classic environment variable-based buffer overflow affecting legacy Linux graphics libraries.
Affected products
- svgalib svgalib 1.2.10 and earlier
Timeline
- 1997-06-19: disclosed: Initial publication date