CVE-2021-4278

Prototype pollution via unsafe path traversal

Published Dec 25, 2022 · Updated Aug 3, 2024

Prototype pollution in Cronvel Tree Kit before 0.7.0 allows local users to modify shared object prototypes through crafted paths. The path and dotPath setters follow the prototype accessor and function-valued path segments, then write attacker-chosen values into the reached prototype object. Exploitation requires an application to pass an untrusted path to a mutating helper; resulting property changes affect objects sharing that prototype.

CVSS severity7.8
High
EPSS probability0.43%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Prototype pollution in Cronvel Tree Kit before 0.7.0 allows local users to modify shared object prototypes through crafted paths. The path and dotPath setters follow the prototype accessor and function-valued path segments, then write attacker-chosen values into the reached prototype object. Exploitation requires an application to pass an untrusted path to a mutating helper; resulting property changes affect objects sharing that prototype.

The record

CVE
CVE-2021-4278
Published
Dec 25, 2022
Updated
Aug 3, 2024
Vendor
Cronvel
Product
Tree Kit
Classifications
CWE-1321
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Dec 25, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0.1
  2. Affected versionversion=0.2
  3. Affected versionversion=0.3
  4. Affected versionversion=0.4
  5. Affected versionversion=0.5
  6. Affected versionversion=0.6

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Cronvel · Tree Kitversion=0.1; version=0.2; version=0.3; version=0.4; version=0.5; version=0.6

Published CVSS scores

7.8GitHub Advisory DatabaseCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-1321Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo