CVE-2020-11059: 
JavaScript vulnerability analysis and mitigation

The vulnerability CVE-2020-11059 affects the aegir npm package, specifically versions 21.7.0 and above, until version 21.10.1. This critical security issue was discovered and disclosed on May 22, 2020, where the aegir publish and aegir build commands could potentially expose sensitive information by leaking secrets from environmental variables in the browser bundle published to npm (GitHub Advisory).

The vulnerability is classified as Critical severity, affecting the build and publish functionality of the aegir package. The issue specifically involves the exposure of environment variables during the browser bundle creation process, which could lead to the inadvertent publication of sensitive information to npm (GitHub Advisory).

The primary impact of this vulnerability is the potential exposure of sensitive information contained in environment variables. When using the affected aegir publish or aegir build commands, secrets stored in environmental variables could be leaked in the browser bundle that gets published to npm, potentially exposing sensitive credentials or configuration data (GitHub Advisory).

The vulnerability could be exploited by examining the published browser bundles for exposed environment variables. Any secrets contained in the environment during the build or publish process could potentially be exposed (GitHub Advisory).

Users are advised to upgrade to aegir version 21.10.1 or later, which contains the patch for this vulnerability. As a workaround, users should run the printenv command to check their environment variables and revoke any potentially exposed secrets. It's recommended to audit any previously published packages for leaked information (GitHub Advisory).