# Improperly Implemented path matching for in-toto-golang

Advisory record · `GHSA-vrxp-mg9f-hwf3`

- **Identifiers:** `GHSA-vrxp-mg9f-hwf3` · `CVE-2021-41087` · `GO-2022-0936`
- **State:** Confirmed
- **Severity:** CVSS 5.6 Medium
- **Critical:** No
- **Weakness (CWE):** [CWE-22](https://cwe.mitre.org/data/definitions/22.html) · [CWE-345](https://cwe.mitre.org/data/definitions/345.html)
- **Tags:** [Path traversal](https://agentprime.io/advisories/tag/path-traversal.md) · [CWE-345](https://agentprime.io/advisories/tag/cwe-345.md)
- **Published:** 22 Sept 2021
- **Updated:** 8 Jul 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 22 Sept 2021, 20:37 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `github.com/in-toto/in-toto-golang` (Go): affected `<0.3.0`; fixed in `0.3.0`

## Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

> The in-toto-golang Go package, versions before 0.3.0, has improper path matching. An authenticated attacker acting as a functionary, who holds trusted private keys, can create attestations that include a disallowed artifact by using path traversal sequences, bypassing DISALLOW rules in the layout. Upgrade to version 0.3.0 or later; the source lists no workaround beyond noting that exploitation depends on the policy applied.

Written 6 Nov 2026.

## Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

## Severity and exploitation

- 5.6 Medium, CVSS 3.1: `CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:N/I:H/A:N`, from CNA (GitHub_M)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0043, the 37th percentile, on 12 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 31 Oct 2026, 15:05 UTC: First seen by agentprime
- 31 Oct 2026, 15:05 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-vrxp-mg9f-hwf3)

## Sources

- [GitHub Advisory Database: GHSA-vrxp-mg9f-hwf3](https://github.com/advisories/GHSA-vrxp-mg9f-hwf3)
- [OSV: GHSA-vrxp-mg9f-hwf3](https://osv.dev/vulnerability/GHSA-vrxp-mg9f-hwf3)
- <https://github.com/in-toto/in-toto-golang/security/advisories/GHSA-vrxp-mg9f-hwf3>
- <https://nvd.nist.gov/vuln/detail/CVE-2021-41087>
- <https://github.com/in-toto/in-toto-golang/commit/f2c57d1e0f15e3ffbeac531829c696b72ecc4290>
- <https://github.com/in-toto/in-toto-golang>

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.

## Check whether this affects you

A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: <https://agentprime.io/mcp.md>
- In a browser: <https://agentprime.io/check/> reads your lockfile in the browser, never uploading it.
- Whether it touches your code, with file and line: the Claude Code plugin, <https://agentprime.io/plugin.md>
- As JSON: <https://api.agentprime.io/v1/advisories/GHSA-vrxp-mg9f-hwf3>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

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The web page: <https://agentprime.io/advisories/GHSA-vrxp-mg9f-hwf3/>. Everything for agents: <https://agentprime.io/llms.txt>.