CVE-2025-58758: Datahihi1 TinyEnv Disclosure Flaw

CVE-2025-58758 Overview

CVE-2025-58758 affects TinyEnv, an environment variable loader library for PHP applications maintained by datahihi1. The vulnerability exists in versions 1.0.1, 1.0.2, 1.0.9, and 1.0.10, where the library does not require the .env file to exist when loading environment variables. Applications that depend on TinyEnv to populate configuration silently continue executing when the file is missing. This behavior can introduce insecure defaults or deployment misconfigurations across production systems. The maintainer addressed the issue in version 1.0.11 by enforcing presence checks on the configuration file.

Critical Impact

Applications relying on TinyEnv may operate with missing security-relevant configuration, resulting in insecure defaults that attackers can leverage through misconfigured deployments.

Affected Products

• TinyEnv 1.0.1
• TinyEnv 1.0.2
• TinyEnv 1.0.9 and 1.0.10

Discovery Timeline

• 2025-09-09 - CVE-2025-58758 published to the National Vulnerability Database (NVD)
• 2025-10-08 - Last updated in the NVD database

Technical Details for CVE-2025-58758

Vulnerability Analysis

TinyEnv is a lightweight PHP library that loads key-value configuration from a .env file into environment variables. The vulnerable versions invoke the loader without first verifying that the target file exists on disk. When the file is absent, the loader returns without raising an exception or warning, leaving the application to run with whatever defaults are baked into the code.

The weakness is classified under CWE-703: Improper Check or Handling of Exceptional Conditions. The library treats a missing configuration file as a normal control flow path rather than an error condition. Downstream code that expects values such as database credentials, API keys, debug flags, or feature toggles instead receives unset variables, which often resolve to empty strings or framework defaults.

Root Cause

The root cause is the absence of a filesystem existence check before the parser opens the .env file. The fix committed in 69b7b885e6cfbf07f470fb3512360e0caa95521e introduces explicit validation so the loader fails loudly when the file cannot be located. See the GitHub Commit Details for the exact change.

Attack Vector

An attacker does not directly exploit TinyEnv over the network. Instead, the flaw becomes a security risk when a deployment ships without its .env file or when the file is removed or renamed during operations. The application boots with insecure defaults — for example, debug mode left enabled, empty authentication secrets, or fallback database connections — and a remote attacker interacting with the affected service can take advantage of those weakened settings. The GitHub Security Advisory GHSA-3j7m-5g4q-gfpc documents the issue.

Detection Methods for CVE-2025-58758

Indicators of Compromise

• Application logs showing successful startup despite the absence of .env on disk
• Runtime configuration values resolving to empty strings or framework defaults in production
• Composer manifests pinning datahihi1/tiny-env to versions 1.0.1, 1.0.2, 1.0.9, or 1.0.10

Detection Strategies

• Inventory PHP projects and scan composer.lock files for vulnerable TinyEnv versions
• Add startup assertions that verify critical environment variables are populated and fail fast if they are not
• Review CI/CD deployment artifacts to confirm the .env file is shipped with each release

Monitoring Recommendations

• Alert on application boot events where required configuration keys are missing or empty
• Track web requests that succeed against endpoints expected to require authentication secrets
• Monitor file integrity of .env paths in production hosts and container images

How to Mitigate CVE-2025-58758

Immediate Actions Required

• Upgrade datahihi1/tiny-env to version 1.0.11 or later through Composer
• Audit production deployments to confirm a valid .env file is present before traffic is served
• Rotate any credentials that may have been exposed through insecure defaults during the vulnerable window

Patch Information

The maintainer released version 1.0.11, which adds a presence check for the .env file before parsing. The complete fix is published in commit 69b7b885e6cfbf07f470fb3512360e0caa95521e and described in the GitHub Security Advisory GHSA-3j7m-5g4q-gfpc.

Workarounds

• Manually verify the existence of the .env file before initializing TinyEnv in application bootstrap code
• Wrap the loader call with explicit error handling that terminates startup if configuration is incomplete
• Enforce required configuration keys at deployment time using infrastructure-as-code validation

# Configuration example: upgrade TinyEnv and validate the .env file at boot
composer require datahihi1/tiny-env:^1.0.11

# Pre-flight check in PHP bootstrap
php -r "if (!file_exists(__DIR__.'/.env')) { fwrite(STDERR, 'Missing .env'); exit(1); }"