MrSwitch hello.js 1.18.6 hello.utils.extend prototype pollution

CVSS Meta Temp Score
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CTI Interest Score
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7.0$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, has been found in MrSwitch hello.js 1.18.6. This impacts the function hello.utils.extend. The manipulation leads to prototype pollution. This vulnerability is listed as CVE-2021-26505. The attack may be initiated remotely. There is no available exploit.

Detailsinfo

A vulnerability was found in MrSwitch hello.js 1.18.6 (JavaScript Library) and classified as problematic. This issue affects the function hello.utils.extend. The manipulation with an unknown input leads to a prototype pollution vulnerability. Using CWE to declare the problem leads to CWE-1321. The product receives input from an upstream component that specifies attributes that are to be initialized or updated in an object, but it does not properly control modifications of attributes of the object prototype. Impacted is integrity. The summary by CVE is:

Prototype pollution vulnerability in MrSwitch hello.js version 1.18.6, allows remote attackers to execute arbitrary code via hello.utils.extend function.

The weakness was presented 08/11/2023 as 634. The advisory is shared at github.com. The identification of this vulnerability is CVE-2021-26505 since 02/01/2021. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1059 for this issue.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2023-2286). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.1
VulDB Meta Temp Score: 7.1

VulDB Base Score: 4.3
VulDB Temp Score: 4.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Prototype pollution
CWE: CWE-1321 / CWE-94 / CWE-74
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

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: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

02/01/2021 🔍
08/11/2023 +920 days 🔍
08/11/2023 +0 days 🔍
07/27/2025 +716 days 🔍

Sourcesinfo

Product: github.com

Advisory: 634
Status: Confirmed

CVE: CVE-2021-26505 (🔍)
GCVE (CVE): GCVE-0-2021-26505
GCVE (VulDB): GCVE-100-236993
EUVD: 🔍

Entryinfo

Created: 08/11/2023 17:53
Updated: 07/27/2025 04:27
Changes: 08/11/2023 17:53 (39), 09/08/2023 10:50 (11), 07/27/2025 04:27 (16)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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