CVE-2025-9288: Browserify Sha.js Input Validation Flaw

CVE-2025-9288 Overview

CVE-2025-9288 is an Improper Input Validation vulnerability affecting sha.js, a popular JavaScript implementation of the SHA family of hash algorithms used in the browserify ecosystem. The vulnerability allows attackers to manipulate input data, potentially compromising the integrity of cryptographic hash operations across applications that depend on this library.

Critical Impact

This vulnerability enables Input Data Manipulation attacks against sha.js through version 2.4.11, potentially allowing attackers to bypass security controls that rely on hash verification, compromise data integrity checks, and affect downstream systems that depend on accurate cryptographic operations.

Affected Products

• browserify sha.js (through version 2.4.11)
• Node.js applications using sha.js for cryptographic hashing
• Browser-based applications bundled with vulnerable sha.js versions

Discovery Timeline

• August 20, 2025 - CVE-2025-9288 published to NVD
• November 3, 2025 - Last updated in NVD database

Technical Details for CVE-2025-9288

Vulnerability Analysis

This vulnerability stems from improper input validation in sha.js, a streaming hashing library that implements SHA-1, SHA-224, SHA-256, SHA-384, and SHA-512 algorithms for use in both Node.js and browser environments. The library fails to properly validate certain input data before processing, which allows attackers to manipulate the hashing operation through specially crafted inputs.

The network-accessible attack vector means that applications using sha.js to hash user-supplied data are particularly at risk. When exploited, this vulnerability can lead to high integrity and availability impacts, potentially allowing attackers to forge hash values or cause denial of service conditions. Additionally, the vulnerability has been identified as having scope change implications, meaning that exploitation could affect systems beyond the vulnerable component itself.

Root Cause

The root cause of CVE-2025-9288 is classified as CWE-20 (Improper Input Validation). The sha.js library does not adequately validate or sanitize input data before incorporating it into hash computations. This lack of proper input validation creates an exploitable condition where malformed or specially crafted input can manipulate the internal state of the hashing algorithm, leading to incorrect hash outputs or other unintended behaviors.

Attack Vector

The vulnerability is exploitable over the network, though it requires some complexity to successfully exploit (high attack complexity with prerequisite conditions). An attacker does not require authentication or user interaction to attempt exploitation. The attack involves:

1. Identifying an application that uses sha.js to hash user-controllable data
2. Crafting malicious input that exploits the improper validation logic
3. Submitting the crafted input to the target application
4. The sha.js library processes the input incorrectly, resulting in manipulated hash outputs

The vulnerability can be exploited against any application that passes untrusted data to sha.js for hashing, including authentication systems, file integrity verification, and data signing operations. Technical details are available in the GitHub Security Advisory.

Detection Methods for CVE-2025-9288

Indicators of Compromise

• Unexpected hash mismatches in systems that previously worked correctly
• Anomalous input patterns submitted to endpoints that perform hash operations
• Application logs showing unusual input sizes or characters being passed to hashing functions
• Failed integrity checks or authentication anomalies where hash comparisons are involved

Detection Strategies

• Audit your Node.js dependencies using npm audit or yarn audit to identify vulnerable sha.js versions
• Implement Software Composition Analysis (SCA) tools to continuously monitor for vulnerable dependencies
• Review application logs for unusual patterns in data submitted to hash-generating endpoints
• Deploy runtime application self-protection (RASP) solutions to detect input manipulation attempts

Monitoring Recommendations

• Enable verbose logging for applications that perform cryptographic operations using sha.js
• Monitor for sudden increases in hash computation errors or integrity check failures
• Set up alerts for dependency vulnerability notifications from npm security advisories
• Implement anomaly detection for API endpoints that accept user input for hashing

How to Mitigate CVE-2025-9288

Immediate Actions Required

• Identify all applications and services using sha.js in your environment
• Review the GitHub Pull Request #78 for patch details
• Update sha.js to a patched version when available
• Consider implementing additional input validation at the application layer as a defense-in-depth measure

Patch Information

A fix has been developed and is tracked in GitHub Pull Request #78. Security details are documented in the GitHub Security Advisory GHSA-95m3-7q98-8xr5. Organizations using Debian-based systems should also monitor the Debian LTS Announcement for distribution-specific patches.

To update sha.js in your Node.js project:

# Check current sha.js version
npm list sha.js

# Update to latest version
npm update sha.js

# Or explicitly install the patched version
npm install sha.js@latest

Workarounds

• Implement strict input validation before passing data to sha.js hash functions
• Consider using alternative cryptographic libraries such as Node.js native crypto module until a patch is applied
• Isolate applications using vulnerable sha.js versions from direct user input where possible
• Apply Web Application Firewall (WAF) rules to filter potentially malicious input patterns

# Configuration example - Audit and lock dependencies
# Run npm audit to identify vulnerable packages
npm audit

# Generate a lockfile to pin dependencies
npm shrinkwrap

# Use npm-force-resolutions to override nested dependencies if needed
# Add to package.json:
# "resolutions": {
#   "sha.js": ">=2.4.12"
# }