Prototype Pollution in Hello.js Project

CVE-2021-26505

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

Vulnerability class: Prototype Pollution

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.011 (66.5th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 66th percentile — 66.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2021-26505: held from 0.011 to 0.011.

EPSS over last 30 days · oldest: 0.011 · newest: 0.011 · change: 0.000

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-26505?
CVE-2021-26505 is a critical-severity vulnerability in Hello.js Project, classified under Improperly Controlled Modification of Object Prototype Attributes (Prototype Pollution). CVSS score: 9.8/10. Published 2023-08-11.
How severe is CVE-2021-26505?
Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2021-26505 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.