Public proof of conceptFix available

CVE-2021-4428

Q: Is CVE-2021-4428 actively exploited?

Active exploitation of CVE-2021-4428 has not been confirmed. Its EPSS score was 15.8% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

Q: What is the CVSS score for CVE-2021-4428?

CVE-2021-4428 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

A public proof of concept exists; no exploitation attested.

Published2023-07-18
Fixed in4.0.1
WeaknessCWE-200

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 vulnerability has been found in what3words Autosuggest Plugin up to 4.0.0 on WordPress and classified as problematic. Affected by this vulnerability is the function enqueue_scripts of the file w3w-autosuggest/public/class-w3w-autosuggest-public.php of the component Setting Handler. The manipulation leads to information disclosure. The attack can be launched remotely. Upgrading to version 4.0.1 is able to address this issue. The patch is named dd59cbac5f86057d6a73b87007c08b8bfa0c32ac. It is recommended to upgrade the affected component. The associated identifier of this vulnerability is VDB-234247.

Timeline

dates in UTC

2023-07-1817:15CVE publishedNVD
2026-10-2319:23First public proof of conceptPoC-in-GitHub
2026-10-2319:23EPSS crossed 10 %FIRST EPSS

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-4428?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-4428?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD

What3words autosuggest

Branch	Affected	Fixed in	Source
4.0	< 4.0.1	4.0.1	NVD

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

Fix

Update What3words autosuggest to 4.0.1

Advisories and patches

github.comPatch
github.comPatch · Vendor Advisory
github.comRelease Notes

Detection

read 2026-10-23 19:23 UTC

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: 1 repository, unverifiedCERT-hr/Log4Shell

Sources

CNACVSS 3.12.7read 2026-10-23
NVDCVSS 3.17.5read 2026-10-23
CNACVSS 2.03.3read 2026-10-23
CNAweakness (CWE)CWE-200read 2026-10-23
FIRST EPSSEPSS score15.8 %read 2026-10-23
PoC-in-GitHubproof of concept1read 2026-10-23

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Published: 2023-07-18
Last Modified: 2026-06-17
NVD status: Modified

Frequently asked questions

What is CVE-2021-4428?

Is CVE-2021-4428 actively exploited?

Active exploitation of CVE-2021-4428 has not been confirmed. Its EPSS score was 15.8% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-4428?

CVE-2021-4428 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

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