Prototype Pollution Vulnerability in 1024bit Extend-Deep by Unknown Vendor
CVE-2026-6621

6.9MEDIUM

Key Information:

Vendor

1024bit

Status
Extend-deep
Vendor
CVE Published:
20 April 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-6621?

A vulnerability exists in the 1024bit Extend-Deep library, particularly in the index.js file, where the manipulation of the proto argument can lead to uncontrolled modifications of object prototype attributes. This weakness can be remotely exploited due to the insufficient handling and validation of input, allowing an attacker to manipulate object properties. It is noteworthy that the library has not seen updates for an extended period, increasing the risks associated with this vulnerability.

Affected Version(s)

extend-deep 0.1.0

extend-deep 0.1.1

extend-deep 0.1.2

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-6621 - Proof of Concept

References

https://vuldb.com/vuln/358256
vdb-entrytechnical-description
https://vuldb.com/vuln/358256/cti
signaturepermissions-required
https://vuldb.com/submit/792387
third-party-advisory

CVSS V4

Score:
6.9
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

sudosme (VulDB User)
VulDB CNA Team
.