# \`tinymember\` was removed from crates.io due to affiliation with malicious code

Advisory record · `RUSTSEC-2026-0263`

- **Identifiers:** `RUSTSEC-2026-0263`
- **State:** Confirmed
- **Severity:** No CVSS score
- **Critical:** No
- **Published:** 20 Aug 2026
- **Updated:** 20 Aug 2026
- **Reviewed by a person:** No

Published by OSV at 20 Aug 2026, 12:00 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `tinymember` (crates.io): affected `>=0.0.0-0`; no fixed version yet

## Machine-written summary

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

> The tinymember crate on crates.io has no fixed version listed. The source says it did not itself contain malicious code but was owned by the same user as the arone and aronenao crates, which contained suspicious build scripts, and it was removed from crates.io. No attack by users is described; the source gives no details on what the build scripts did, and no fix or workaround is listed.

Written 8 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

No source has published a CVSS score for this record yet.

- **CISA KEV:** Not listed.
- **EPSS:** No score.

## Timeline

- 31 Oct 2026, 15:18 UTC: First seen by agentprime
- 31 Oct 2026, 15:18 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/RUSTSEC-2026-0263)

## Sources

- [OSV: RUSTSEC-2026-0263](https://osv.dev/vulnerability/RUSTSEC-2026-0263)
- <https://crates.io/crates/tinymember>
- <https://rustsec.org/advisories/RUSTSEC-2026-0263.html>
- <https://blog.rust-lang.org/2026/08/20/supply-chain-attack-on-arrayref>

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/RUSTSEC-2026-0263>, 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/RUSTSEC-2026-0263/>. Everything for agents: <https://agentprime.io/llms.txt>.