CVE-2026-8261
Heap-based Buffer Overflow in Squirrel up to 3.2
Publication date: 2026-05-11
Last updated on: 2026-05-11
Assigner: VulDB
Description
Description
CVSS Scores
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Meta Information
Affected Vendors & Products
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-122 | A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). |
| CWE-119 | The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data. |
Attack-Flow Graph
AI Powered Q&A
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
The provided information does not specify any direct impact of this vulnerability on compliance with common standards and regulations such as GDPR or HIPAA.
Can you explain this vulnerability to me?
CVE-2026-8261 is a heap-based buffer overflow vulnerability in the Squirrel scripting language up to version 3.2. It occurs in the function SQFunctionProto::Load within the file squirrel/sqobject.cpp. The issue arises due to an integer overflow in the _FUNC_SIZE macro during bytecode loading, which causes an undersized buffer allocation. Specifically, unvalidated count fields from a bytecode stream lead to a buffer that is too small, and when the program attempts to write data into this buffer, it overflows the heap.
This vulnerability can be triggered by loading a specially crafted .cnut bytecode file via functions like sqstd_loadfile or sq_readclosure. The root cause is the lack of bounds checking on count fields read from the bytecode stream, which allows an attacker to manipulate the size calculations and cause the overflow.
How can this vulnerability impact me? :
This vulnerability can lead to arbitrary code execution or denial-of-service conditions if exploited. Since it is a heap buffer overflow triggered by loading crafted bytecode files, an attacker with local access could exploit this flaw to execute malicious code or crash the application using the Squirrel scripting language.
The attack is restricted to local execution, meaning remote exploitation is not indicated. However, local attackers or users who can supply malicious bytecode files could leverage this vulnerability to compromise the affected system.
How can this vulnerability be detected on my network or system? Can you suggest some commands?
This vulnerability is triggered by loading a specially crafted .cnut bytecode file via functions like sqstd_loadfile or sq_readclosure in the Squirrel scripting language up to version 3.2.
Detection would involve identifying attempts to load suspicious or crafted .cnut files locally, as the attack is restricted to local execution.
Since the vulnerability is related to heap buffer overflow caused by integer overflow in bytecode loading, monitoring or scanning for unusual or malformed .cnut files being loaded by Squirrel processes could help.
No specific detection commands are provided in the available resources.
What immediate steps should I take to mitigate this vulnerability?
Immediate mitigation steps include preventing the loading of untrusted or crafted .cnut bytecode files in the Squirrel environment.
Since the vulnerability is exploitable only via local execution, restricting local access to systems running vulnerable versions of Squirrel can reduce risk.
A suggested fix involves replacing the vulnerable _FUNC_SIZE macro with overflow-checked arithmetic or enforcing maximum limits on count fields immediately after reading them, but this requires patching the source code.
As the project has not yet responded with an official patch, monitoring for updates and applying patches once available is recommended.