Executive Summary

[{'type': 'paragraph', 'content': "CVE-2026-4010 is a memory corruption vulnerability in the function pkByteBufferAddString of ThakeeNathees' pocketlang. It occurs when the function processes an argument length with the value 4294967290, which is an integer underflow leading to an extremely large length value."}, {'type': 'paragraph', 'content': 'This causes the program to write beyond the allocated buffer size, resulting in a heap buffer overflow and segmentation fault (crash). The vulnerability is triggered when the compiler tries to report a "Non terminated string" error, and the error-reporting logic itself causes the overflow.'}, {'type': 'paragraph', 'content': 'Additional related issues include null function pointer dereference during parsing and type confusion causing invalid memory access, all leading to crashes and potential exploitation.'}] [1, 2, 4]

Useful 0 Not Useful 0

Impact Analysis

This vulnerability can cause the pocketlang compiler or runtime to crash due to memory corruption, resulting in denial of service.

Since the attack requires local access and specially crafted malformed input, an attacker with local access could exploit this to disrupt system availability.

The impact is primarily on system stability and availability, as the memory corruption leads to segmentation faults and crashes.

Useful 0 Not Useful 0

Compliance Impact

I don't know

Useful 0 Not Useful 0

Detection Guidance

[{'type': 'paragraph', 'content': 'This vulnerability can be detected by running the pocketlang compiler with specially crafted malformed input scripts that trigger the error conditions leading to crashes.'}, {'type': 'paragraph', 'content': 'Specifically, the crash occurs when the compiler tries to report a "Non terminated string" error, causing an integer underflow and heap buffer overflow in the function pkByteBufferAddString.'}, {'type': 'paragraph', 'content': 'Detection involves compiling or running pocketlang on Linux x86_64 with Clang in Release mode using malformed scripts that cause segmentation faults (SIGSEGV) at specific source code locations such as src/core/value.c:40.'}, {'type': 'paragraph', 'content': 'Using debugging tools like GDB to observe crashes at pkByteBufferAddString or related functions during compilation of malformed inputs can confirm the presence of the vulnerability.'}, {'type': 'list_item', 'content': 'Run pocketlang compiler with a malformed input file designed to trigger a non-terminated string error.'}, {'type': 'list_item', 'content': 'Use GDB to debug and check for segmentation faults at src/core/value.c line 40 or related crash points.'}] [1, 2]

Useful 0 Not Useful 0

Mitigation Strategies

Currently, there is no official response or patch from the pocketlang project to address this vulnerability.

Immediate mitigation steps include avoiding the use of pocketlang in environments where local users could exploit this vulnerability.

Consider restricting local access to the system or application running pocketlang to trusted users only.

Monitor for any updates or patches from the project and apply them once available.

As no known countermeasures exist, users are advised to consider alternative products if possible.

Useful 0 Not Useful 0