Stack Buffer Overflow Vulnerability in MapServer: Critical Security Flaw
Summary
OSV-2026-1198: Stack-buffer-overflow in msLayoutTextSymbol. Affects mapserver across 2 version ranges.
< 2f88fcd2202ebd643350b63ffad1259b8cc2bbe8
>= c2ec9215037703e029fbd64259977aaabfdbb9e7, < e84d91b4732e35132a28d72ad5f3c962a7acaed5
Fixed in e84d91b4732e35132a28d72ad5f3c962a7acaed5. How to fix ↓
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Background
MapServer is an open-source platform for publishing spatial data and interactive mapping applications on the web. It is widely used for rendering maps and handling geospatial data. The package is known for its flexibility and support for various data formats, making it a popular choice among developers. However, it is susceptible to vulnerabilities that can lead to severe security issues, such as the stack buffer overflow identified in this report.
Vulnerability Detail
The vulnerability identified is a stack buffer overflow in the msLayoutTextSymbol function of MapServer. This issue was reported through OSS-Fuzz, indicating that it can lead to a crash due to an attempt to read beyond the allocated memory space. The crash state shows that the overflow occurs during the processing of text symbols, which could potentially allow an attacker to exploit this flaw to execute arbitrary code or cause denial of service. The vulnerability was introduced in a specific commit and has been fixed in subsequent versions, highlighting the importance of keeping software up to date.
How To Fix
Minimum fixed version
e84d91b4732e35132a28d72ad5f3c962a7acaed5
This is the first release that contains the fix.
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Workaround
As a temporary workaround, you may consider disabling the specific functionality that utilizes text symbols until the package can be updated. This can prevent the vulnerability from being exploited while you work on applying the patch.
Conclusion
The stack buffer overflow vulnerability in MapServer poses a significant risk to applications utilizing this package. It is crucial to update to the patched versions to mitigate potential exploitation. Additionally, using tools like Vulert can help monitor and manage vulnerabilities in your software effectively.
See every vulnerability recorded for mapserver →
FAQ
A stack buffer overflow occurs when a program writes more data to a buffer located on the stack than it can hold, which can lead to memory corruption and potential exploitation.
If exploited, this vulnerability could allow an attacker to execute arbitrary code, leading to unauthorized access, data breaches, or denial of service.
Yes, you can use Vulert, which monitors and alerts for open-source vulnerabilities in real-time. You can check your application against this vulnerability using the Vulert playground without signing up.
If an immediate update is not possible, consider implementing a workaround by disabling the affected functionality or restricting access to the application until the patch can be applied.
Detailed information about this vulnerability can be found in the OSS-Fuzz report and the GitHub repository for MapServer.
References
Related vulnerabilities
Recent vulnerabilities recorded for mapserver.
