CVE-2026-4744
Out-of-Bounds Read in Notepad3 Scintilla Module
Publication date: 2026-03-24
Last updated on: 2026-03-24
Assigner: Government Technology Agency of Singapore Cyber Security Group (GovTech CSG)
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| rizonesoft | notepad3 | to 6.25.714.1 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-125 | The product reads data past the end, or before the beginning, of the intended buffer. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability is an out-of-bounds read issue found in the rizonesoft Notepad3 software, specifically in the program files related to the regcomp.C module which involves regular expression compilation.
The problem originated from a function called compile_string_node(), which was cloned from the Oniguruma regular expression library but had not received a critical security patch that was applied in the original PHP source code. This led to a heap buffer overflow vulnerability in multibyte regular expression functions.
The vulnerability was fixed by applying the same patch from the PHP source repository to the cloned function in Notepad3, eliminating the security risk.
How can this vulnerability impact me? :
This vulnerability can lead to a heap buffer overflow, which may allow an attacker to read memory outside the intended bounds.
Such an out-of-bounds read can cause application crashes, data leakage, or potentially allow an attacker to execute arbitrary code depending on the context and exploitation.
Given the high CVSS score of 9.3, this indicates a severe impact with local attack vector and requires user interaction, but can lead to significant confidentiality, integrity, and availability impacts.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
I don't know
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, you should update Notepad3 to version 6.25.714.1 or later, where the security fix has been applied.
The fix involves applying a security patch to the function compile_string_node(), which addresses a heap buffer overflow vulnerability in the multibyte regular expression functions.
Ensuring your Notepad3 installation is updated to the patched version will eliminate the security risk associated with this out-of-bounds read vulnerability.