Starcounter-Jack JSON-Patch up to 3.1.0 prototype pollution

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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A vulnerability has been found in Starcounter-Jack JSON-Patch up to 3.1.0 and classified as problematic. This vulnerability affects some unknown functionality. The manipulation with an unknown input leads to a prototype pollution vulnerability. The CWE definition for the vulnerability is CWE-1321. The software 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. As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was presented 12/25/2022 as 262. The advisory is available at This vulnerability was named CVE-2021-4279. Technical details are unknown but a public exploit is available. This vulnerability is assigned to T1059 by the MITRE ATT&CK project.

It is possible to download the exploit at It is declared as proof-of-concept.

Upgrading to version 3.1.1 eliminates this vulnerability. The upgrade is hosted for download at Applying the patch 7ad6af41eabb2d799f698740a91284d762c955c9 is able to eliminate this problem. The bugfix is ready for download at The best possible mitigation is suggested to be upgrading to the latest version.





  • open-source

CPE 2.3info

CPE 2.2info


VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.3

VulDB Base Score: 6.3
VulDB Temp Score: 5.7
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔒

CNA Base Score: 6.3
CNA Vector (VulDB): 🔒



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


Class: Prototype pollution
CWE: CWE-1321 / CWE-94 / CWE-74
ATT&CK: T1059

Local: No
Remote: Yes

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒


Threat Intelligenceinfo

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


Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: JSON-Patch 3.1.1
Patch: 7ad6af41eabb2d799f698740a91284d762c955c9


12/25/2022 Advisory disclosed
12/25/2022 +0 days CVE reserved
12/25/2022 +0 days VulDB entry created
01/24/2023 +30 days VulDB last update


Advisory: 262
Status: Confirmed

CVE: CVE-2021-4279 (🔒)
scip Labs:


Created: 12/25/2022 08:46 PM
Updated: 01/24/2023 11:09 AM
Changes: 12/25/2022 08:46 PM (45), 01/24/2023 10:57 AM (2), 01/24/2023 11:02 AM (21), 01/24/2023 11:09 AM (1)
Complete: 🔍


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