Winters <= 1.4.3 - Prototype Pollution to Reflected Cross-Site Scripting

published 2023-10-20 3 y ago modified 2026-06-17 4 mo ago also EUVD-2023-44587

cvss: 6.1; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 39%
public exploits: 0; none known

The Winters theme for WordPress is vulnerable to Reflected Cross-Site Scripting via prototype pollution in versions up to, and including, 1.4.3 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link.

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 21 mo ago (2025-02-05)

Exploit prediction

0.45% chance of exploitation in the next 30 days, higher than 39% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	6.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
NVD	3.1	6.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Affected products

myshopkit Winters - WordPress Blog Theme

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation
CWE-1321 Improperly Controlled Modification of Object Prototype Attributes

Technology feeds

WordPress rss critical rss

References

wordfence.com /threat-intel/vulnerabilities/id/6f8b75a1-f0f2-445b-a1c7-1628916470d3?source=cve
third-party-advisory
github.com /BlackFan/client-side-prototype-pollution
not-applicable

Sources

CVE List CVE-2023-3962
NVD CVE-2023-3962

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary