Notepad++ up to 8.5.6 NextStater buffer overflow

CVSS Meta Temp Score
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CTI Interest Score
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5.3$0-$5k0.00

Summaryinfo

A vulnerability was found in Notepad++ up to 8.5.6. It has been rated as critical. The impacted element is the function nsCodingStateMachine::NextStater. The manipulation leads to buffer overflow. This vulnerability is documented as CVE-2023-40164. The attack needs to be performed locally. There is not any exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Notepad++ up to 8.5.6 (Document Reader Software) and classified as critical. This issue affects the function nsCodingStateMachine::NextStater. The manipulation with an unknown input leads to a buffer overflow vulnerability. Using CWE to declare the problem leads to CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Notepad++ is a free and open-source source code editor. Versions 8.5.6 and prior are vulnerable to global buffer read overflow in `nsCodingStateMachine::NextStater`. The exploitability of this issue is not clear. Potentially, it may be used to leak internal memory allocation information. As of time of publication, no known patches are available in existing versions of Notepad++.

The weakness was released 08/26/2023 as GHSL-2023-092. It is possible to read the advisory at securitylab.github.com. The identification of this vulnerability is CVE-2023-40164 since 08/09/2023. Technical details of the vulnerability are known, but there is no available exploit.

Upgrading to version 8.5.7 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 5.5
CNA Vector (GitHub, Inc.): 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Notepad++ 8.5.7

Timelineinfo

08/09/2023 🔍
08/26/2023 +17 days 🔍
08/26/2023 +0 days 🔍
02/03/2026 +892 days 🔍

Sourcesinfo

Advisory: GHSL-2023-092
Status: Confirmed

CVE: CVE-2023-40164 (🔍)
GCVE (CVE): GCVE-0-2023-40164
GCVE (VulDB): GCVE-100-238091

Entryinfo

Created: 08/26/2023 13:34
Updated: 02/03/2026 16:17
Changes: 08/26/2023 13:34 (49), 02/03/2026 16:14 (1), 02/03/2026 16:15 (1), 02/03/2026 16:17 (19)
Complete: 🔍
Committer: lywand
Cache ID: 216::103

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