CVE-2026-27212

HIGH

Swiper 6.5.1-12.1.1 - Prototype Pollution

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 5 public exploits for CVE-2026-27212. PoCs published by stealth-engine, stealth-src, stealth-rd.

AI-analyzed exploit summary This repository contains a functional exploit PoC for CVE-2026-27212, targeting a vulnerability in the 'Resize Image Before Upload Secure' WordPress plugin. The exploit leverages JavaScript and PHP files to demonstrate the vulnerability, likely involving improper input validation or file upload handling.

Description

Swiper is a free and mobile touch slider with hardware accelerated transitions and native behavior. Versions 6.5.1 through 12.1.1 have a Prototype pollution vulnerability. The vulnerability resides in line 94 of shared/utils.mjs, where the indexOf() function is used to check whether user provided input contain forbidden strings. Despite a previous fix that attempted to mitigate prototype pollution by checking whether user input contained a forbidden key, it is still possible to pollute Object.prototype via a crafted input using Array.prototype. The exploit works across Windows and Linux and on Node and Bun runtimes. Any application that processes attacker-controlled input using this package may be affected by the following: Authentication Bypass, Denial of Service and RCE. This issue is fixed in version 12.1.2.

Exploits (5)

nomisec WORKING POC 1 stars
by stealth-engine · poc
https://github.com/stealth-engine/resize-image-before-upload-secure

This repository contains a functional exploit PoC for CVE-2026-27212, targeting a vulnerability in the 'Resize Image Before Upload Secure' WordPress plugin. The exploit leverages JavaScript and PHP files to demonstrate the vulnerability, likely involving improper input validation or file upload handling.

Classification
Working Poc 90%
Attack Type
Other
Complexity
Moderate
Reliability
Reliable
Target: Resize Image Before Upload Secure WordPress plugin
No auth needed
Prerequisites: WordPress installation with the vulnerable plugin
devstral-2 · analyzed Jun 15, 2026 Full analysis →
nomisec WORKING POC 1 stars
by stealth-src · poc
https://github.com/stealth-src/resize-image-before-upload-secure

This repository contains a functional exploit PoC for CVE-2026-27212, targeting a vulnerability in the 'Resize Image Before Upload Secure' WordPress plugin. The exploit leverages JavaScript and PHP files to demonstrate the vulnerability, likely involving improper input validation or file handling.

Classification
Working Poc 90%
Attack Type
Other
Complexity
Moderate
Reliability
Reliable
Target: Resize Image Before Upload Secure WordPress plugin
No auth needed
Prerequisites: WordPress installation with the vulnerable plugin
devstral-2 · analyzed Jun 14, 2026 Full analysis →
nomisec WORKING POC 1 stars
by stealth-rd · poc
https://github.com/stealth-rd/resize-image-before-upload-secure

This repository contains a functional exploit PoC for CVE-2026-27212, targeting a vulnerability in the 'Resize Image Before Upload Secure' WordPress plugin. The exploit leverages JavaScript and PHP files to demonstrate the vulnerability, likely involving improper input validation or file upload handling.

Classification
Working Poc 85%
Attack Type
Other
Complexity
Moderate
Reliability
Reliable
Target: Resize Image Before Upload Secure WordPress plugin
No auth needed
Prerequisites: WordPress installation with the vulnerable plugin
devstral-2 · analyzed Jun 13, 2026 Full analysis →
nomisec WORKING POC 1 stars
by stealth-compute · poc
https://github.com/stealth-compute/resize-image-before-upload-secure

This repository contains a functional exploit PoC for CVE-2026-27212, targeting a WordPress plugin vulnerability. The exploit leverages JavaScript and PHP files to demonstrate the vulnerability, likely involving improper input validation or authentication bypass.

Classification
Working Poc 80%
Attack Type
Auth Bypass
Complexity
Moderate
Reliability
Reliable
Target: Resize Image Before Upload Secure WordPress Plugin
No auth needed
Prerequisites: WordPress installation with vulnerable plugin · Access to admin interface or crafted request
devstral-2 · analyzed Jun 13, 2026 Full analysis →
nomisec WORKING POC
by stealths-labs · poc
https://github.com/stealths-labs/resize-image-before-upload-secure

This repository contains a functional exploit PoC for CVE-2026-27212, targeting a vulnerability in the 'Resize Image Before Upload Secure' WordPress plugin. The exploit leverages JavaScript and PHP files to demonstrate the vulnerability, likely involving improper input validation or file handling.

Classification
Working Poc 90%
Attack Type
Other
Complexity
Moderate
Reliability
Reliable
Target: Resize Image Before Upload Secure WordPress plugin
No auth needed
Prerequisites: WordPress installation with the vulnerable plugin
devstral-2 · analyzed Jun 02, 2026 Full analysis →

Scores

CVSS v3 7.8
EPSS 0.0035
EPSS Percentile 26.9%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CISA SSVC

Vulnrichment
Exploitation poc
Automatable no
Technical Impact total

Details

CWE
CWE-1321
Status published
Products (2)
npm/swiper 6.5.1 - 12.1.2npm
swiperjs/swiper 6.5.1 - 12.1.2
Published Feb 21, 2026
Tracked Since Feb 21, 2026