Skip to content

Comments

fix(deps): update dependency swiper to ^12.1.2 [security]#712

Merged
michnowak merged 1 commit intomainfrom
renovate/npm-swiper-vulnerability
Feb 20, 2026
Merged

fix(deps): update dependency swiper to ^12.1.2 [security]#712
michnowak merged 1 commit intomainfrom
renovate/npm-swiper-vulnerability

Conversation

@renovate
Copy link
Contributor

@renovate renovate bot commented Feb 20, 2026

This PR contains the following updates:

Package Change Age Confidence
swiper (source) ^12.1.0^12.1.2 age confidence

GitHub Vulnerability Alerts

CVE-2026-27212

Summary

A prototype pollution vulnerability exists in the the npm package swiper (>=6.5.1, < 12.1.2). 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. This issue is fixed in version 12.1.2

Details

The vulnerability resides in line 94 of shared/utils.mjs where indexOf() function is used to check whether user provided input contain forbidden strings.

PoC

Steps to reproduce

  1. Install latest version of swiper using npm install
  2. Run the following code snippet:
var swiper = require('swiper');
Array.prototype.indexOf = () => -1;        
let obj = {};
var malicious_payload = '{"__proto__":{"polluted":"yes"}}';
console.log({}.polluted);
swiper.default.extendDefaults(JSON.parse(malicious_payload));
console.log({}.polluted);  // prints yes -> indicating that the patch was bypassed and prototype pollution occurred

Expected behavior

Prototype pollution should be prevented and {} should not gain new properties.
This should be printed on the console:

undefined
undefined OR throw an Error

Actual behavior

Object.prototype is polluted
This is printed on the console:

undefined 
yes

Impact

This is a prototype pollution vulnerability, which can have severe security implications depending on how swiper is used by downstream applications. Any application that processes attacker-controlled input using this package may be affected.
It could potentially lead to the following problems:

  1. Authentication bypass
  2. Denial of service - Even if an attacker is not able to exploit prototype pollution in swiper, if there is a prototype pollution within the project from other dependencies, modifying global Array.prototype.indexOf property can result in crash when swiper.default.extendDefaults is called because swiper makes use of this global property. This can lead to Denial of Service.
  3. Remote code execution (if polluted property is passed to sinks like eval or child_process)

Related CVEs

CVE-2026-25521
CVE-2026-25047
CVE-2026-26021


Release Notes

nolimits4web/Swiper (swiper)

v12.1.2

Compare Source

v12.1.1

Compare Source

Bug Fixes

Configuration

📅 Schedule: Branch creation - "" (UTC), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.


  • If you want to rebase/retry this PR, check this box

This PR was generated by Mend Renovate. View the repository job log.

@vercel
Copy link

vercel bot commented Feb 20, 2026

The latest updates on your projects. Learn more about Vercel for GitHub.

1 Skipped Deployment
Project Deployment Actions Updated (UTC)
o2s-docs Skipped Skipped Feb 20, 2026 7:58am

Request Review

@vercel vercel bot temporarily deployed to Preview – o2s-docs February 20, 2026 07:58 Inactive
@github-actions
Copy link
Contributor

Coverage Report for packages/configs/vitest-config

Status Category Percentage Covered / Total
🔵 Lines 80.87% 1192 / 1474
🔵 Statements 80.34% 1267 / 1577
🔵 Functions 78.66% 446 / 567
🔵 Branches 72.13% 1017 / 1410
File CoverageNo changed files found.
Generated in workflow #340 for commit cd8d456 by the Vitest Coverage Report Action

@michnowak michnowak merged commit ee70196 into main Feb 20, 2026
14 checks passed
@michnowak michnowak deleted the renovate/npm-swiper-vulnerability branch February 20, 2026 11:46
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Labels

None yet

Projects

None yet

Development

Successfully merging this pull request may close these issues.

1 participant