Skip to main content
No exploitation reportedFix available

CVE-2018-16489

No exploitation reported by the sources we read.

  • Published2019-02-01
  • Fixed in4.0.0
  • WeaknessCWE-400 · CWE-74

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

A prototype pollution vulnerability was found in just-extend <4.0.0 that allows attack to inject properties onto Object.prototype through its functions.

Timeline

dates in UTC
  1. 2019-02-0118:29CVE publishedNVD

Versions per branch

NVD · OSV
Just-extend project just-extend
BranchAffectedFixed in
4.0< 4.0.04.0.0

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

  1. Update Just-extend project just-extend to 4.0.0

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof of concept
Metasploit modules
none listed
Metasploit Framework

Sources

  • NVDCVSS 3.19.8read 2026-10-23
  • NVDCVSS 2.07.5read 2026-10-23
  • CNAweakness (CWE)CWE-400known since 2026-10-23
  • NVDweakness (CWE)CWE-74read 2026-10-23
  • FIRST EPSSEPSS score1.8 %2026-11-08
  • OSVaffected packages—
  • GitHub AdvisoriesadvisoryCRITICAL2020-06-16

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Published
2019-02-01
Last Modified
2026-06-17
NVD status
Modified
GitHub Advisory
GHSA-675m-85rw-j3w4

Frequently asked questions

What is CVE-2018-16489?

A prototype pollution vulnerability was found in just-extend <4.0.0 that allows attack to inject properties onto Object.prototype through its functions.

Is CVE-2018-16489 actively exploited?

Active exploitation of CVE-2018-16489 has not been confirmed. Its EPSS score was 1.8% on 2026-11-08, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2018-16489?

CVE-2018-16489 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Running just-extend? Hear about its next vulnerability

Surveillance reads the versions in your stack — a domain, a lockfile or a list — checks each CVE against the ranges its sources publish, and alerts you when one you run is exploited or enters CISA KEV. A version it cannot read stays « version not verified ».

Get alerts for this productCISA KEV additions, November 2026Search CVEs

No credit card required · No monthly cap on website lookups · 250 API requests/month

Go further

Related vulnerabilities

Same product first, then the same vendor advisory and the same publication week.

Back to CVE Database

Sources for this record