filecoin-pin upload GitHub Action lets fork PRs spend the repository owner's Filecoin wallet

Summary

The filecoin-pin upload GitHub Action (filecoin-project/filecoin-pin) before 1.1.0 does not repeat its fork-PR check when run from a privileged workflow_run workflow. In the documented two-workflow pattern, an external contributor's fork pull request can get attacker-controlled artifacts uploaded using the repository owner's Filecoin wallet.

Affected

• filecoin-pin upload GitHub Action, versions prior to 1.1.0 (the 0.x action line receives no backport)
• Fixed in 1.1.0

Impact

Fork detection in upload-action/src/build.js only checks event.pull_request, which is absent under workflow_run, so isForkPR becomes false. The action then initialises the wallet with walletPrivateKey and uploads the untrusted artifact. An external contributor can cause unauthorized storage expenditure, dataset pollution and consumption of the configured wallet's funds. Disclosure of the wallet private key is not required. User interaction (a workflow run on the fork PR) is needed. CVSS 3.1 8.2 (High, AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:L) as assigned by the GitHub CNA. The source does not report exploitation in the wild.

Recommended actions

• Upgrade the action to filecoin-pin 1.1.0 or later; migrate 0.x users to the fixed 1.x line
• Until upgraded, do not run the upload action from workflow_run workflows triggered by fork pull requests
• Review wallet spending and stored datasets for unexpected uploads, and keep only minimal funds in CI wallets

Source & attribution

This 0xCERT advisory summarises a disclosure by the Filecoin Pin maintainers (GHSA-4rpx-vcp4-863j), published as CVE-2026-58412 on NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-58412. Details may change; refer to the original source for the authoritative record.