Capgo CLI EUVD-2026-38165

Exploitation requires the attacker to have pre-placed symbolic links named .capgo or .capgo-credentials.json within a directory where the developer subsequently runs the Capgo CLI. This is most naturally achieved by contributing symlinks to a repository that the developer clones (e.g., a pull request adding .capgo as a symlink, which is a file type git tracks). The developer must then actively invoke one of two specific CLI commands: capgo login [key] --local (triggering Issue 1) or capgo build credentials save --local (triggering Issue 2). No authentication to any remote service is required for exploitation - Issue 2 explicitly occurs even when the user is not logged in. Exploitation is limited to the file system permissions of the developer running the CLI; the attacker cannot overwrite files owned by other users. The permissions exposure (Issue 3) occurs whenever global credentials are saved, even without a symlink, but requires access to the same host to read the credentials.

The CVSS 4.0 base score of 6.8 reflects a local attack vector (AV:L) requiring active user interaction (UI:A), which significantly constrains mass exploitation compared to network-reachable flaws. However, the real-world risk to software development teams is meaningfully higher than the raw score suggests. The attack scenario - a malicious or compromised repository containing planted symlinks - is a well-understood supply chain vector that requires only that a developer clone and operate the CLI, actions performed routinely. The integrity impact is rated High (VI:H) because arbitrary file overwrite is achievable with attacker-chosen content. The confidentiality impact is rated Low (VC:L) for the permissions-leak issue, but in practice, exposure of mobile signing credentials (Android keystore, iOS distribution certificates, Play/App Store API keys) on shared CI runners constitutes a meaningful secret compromise. EPSS data was not provided; exploitation probability cannot be quantified from available sources. No KEV listing confirms active exploitation. A PoC is publicly documented in the GHSA advisory, lowering the bar for exploitation. The version discrepancy between NVD (12.128.2) and GHSA/npm (7.84.6) should be verified - defenders should patch to the highest confirmed fixed version available for their package manager.

An attacker publishes or contributes to a repository containing pre-planted symbolic links: .capgo pointing to a critical developer-owned file such as ~/.ssh/authorized_keys, and .capgo-credentials.json pointing to a shared configuration file. When the developer clones this repository and runs capgo login SOME_KEY --local or capgo build credentials save --local within it, the CLI writes attacker-controlled content directly to the symlink targets - overwriting SSH keys, configuration files, or other sensitive paths. A working PoC for the .capgo clobber path is publicly documented in the GHSA advisory, confirming this scenario is reproducible with minimal effort.