CVE-2026-6621
1024bit extend-deep index.js prototype pollution
Description
A vulnerability was determined in 1024bit extend-deep up to 0.1.6. The impacted element is an unknown function of the file index.js. This manipulation of the argument __proto__ causes improperly controlled modification of object prototype attributes. Remote exploitation of the attack is possible. The exploit has been publicly disclosed and may be utilized. The code repository of the project has not been active for many years.
INFO
Published Date :
April 20, 2026, 9:16 a.m.
Last Modified :
Oct. 26, 2026, 9:10 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 2.0 | HIGH | [email protected] | ||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update extend-deep to a version without the vulnerability.
- Remove or replace the vulnerable library.
- Implement input sanitization and validation.
Public PoC/Exploit Available at Github
CVE-2026-6621 has a 1 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-6621.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-6621 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-6621
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
🔍 Proof-of-Concepts for real-world vulnerabilities
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-6621 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-6621 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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CVE Translated by [email protected]
Oct. 26, 2026
Action Type Old Value New Value Added Translation Title: extend-deep de 1024bit, Description: Se determinó una vulnerabilidad en 1024bit extend-deep hasta 0.1.6. El elemento afectado es una función desconocida del archivo index.js. Esta manipulación del argumento __proto__ provoca una modificación indebidamente controlada de los atributos de prototipo de objeto. La explotación remota del ataque es posible. El exploit ha sido divulgado públicamente y puede utilizarse. El repositorio de código del proyecto no ha estado activo durante muchos años. -
CVE Modified by [email protected]
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'vendor': '1024bit', 'product': 'extend-deep', 'versions': [{'status': 'affected', 'version': '0.1.0'}, {'status': 'affected', 'version': '0.1.1'}, {'status': 'affected', 'version': '0.1.2'}, {'status': 'affected', 'version': '0.1.3'}, {'status': 'affected', 'version': '0.1.4'}, {'status': 'affected', 'version': '0.1.5'}, {'status': 'affected', 'version': '0.1.6'}]}] -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-6621', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-04-20T15:32:28.916284Z'} -
Data Remediation by [email protected]
Apr. 29, 2026
Action Type Old Value New Value Changed CVSS V4.0 Score 6.9 5.5 -
New CVE Received by [email protected]
Apr. 20, 2026
Action Type Old Value New Value Added Description A vulnerability was determined in 1024bit extend-deep up to 0.1.6. The impacted element is an unknown function of the file index.js. This manipulation of the argument __proto__ causes improperly controlled modification of object prototype attributes. Remote exploitation of the attack is possible. The exploit has been publicly disclosed and may be utilized. The code repository of the project has not been active for many years. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L Added CVSS V2 (AV:N/AC:L/Au:N/C:P/I:P/A:P) Added CWE CWE-94 Added CWE CWE-1321 Added Reference https://github.com/sudo-secure/security-research/blob/main/extend-deep/prototype-pollution/PoC.md Added Reference https://vuldb.com/submit/792387 Added Reference https://vuldb.com/vuln/358256 Added Reference https://vuldb.com/vuln/358256/cti