# Vite: First 4 bytes of files outside of \`server.fs\` setting is exposed by \`?vite-wasm-instance\` Advisory record · `GHSA-vfpm-58rq-9qcg` - **Identifiers:** `GHSA-vfpm-58rq-9qcg` · `CVE-2026-112947` - **State:** Confirmed - **Severity:** CVSS 6.3 Medium - **Critical:** No - **Weakness (CWE):** [CWE-22](https://cwe.mitre.org/data/definitions/22.html) · [CWE-200](https://cwe.mitre.org/data/definitions/200.html) · [CWE-209](https://cwe.mitre.org/data/definitions/209.html) - **Tags:** [Path traversal](https://agentprime.io/advisories/tag/path-traversal.md) · [Information disclosure](https://agentprime.io/advisories/tag/info-disclosure.md) - **Published:** 21 Oct 2026 - **Updated:** 21 Oct 2026 - **Reviewed by a person:** No Published by the GitHub Advisory Database at 21 Oct 2026, 16:47 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. ## Affected packages - `vite` (npm): affected `>=8.3.0, <8.3.3 || >=8.2.0, <8.2.4`; fixed in `8.3.3`, `8.2.4` - `vite-plus` (npm): affected `>=0.2.8, <1.1.0`; fixed in `1.1.0` ## Machine-written summary Summary written by Claude Haiku from the source advisory. Not reviewed by a person. > The Vite dev server in the vite package (versions 8.2.0 up to 8.2.4, and 8.3.0 up to 8.3.3) and the vite-plus package (versions 0.2.8 up to 1.1.0) can return the first 4 bytes of files outside the server.fs allow list when a request includes the ?vite-wasm-instance query. The attack requires the dev server to be exposed to the network via --host or server.host, the target file to hold sensitive data in its first 4 bytes, and the project to run Vite on Node.js or Deno rather than Bun. Upgrade vite to 8.2.4 or 8.3.3, and vite-plus to 1.1.0. Written 31 Oct 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 - 6.3 Medium, CVSS 4.0: `CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N`, from CNA (GitHub_M) - **CISA KEV:** Not listed. - **EPSS:** 0.0050, the 43rd percentile, on 6 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days. ## Timeline - 31 Oct 2026, 13:33 UTC: First seen by agentprime - 31 Oct 2026, 13:33 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-vfpm-58rq-9qcg) ## Sources - [GitHub Advisory Database: GHSA-vfpm-58rq-9qcg](https://github.com/advisories/GHSA-vfpm-58rq-9qcg) - [OSV: GHSA-vfpm-58rq-9qcg](https://osv.dev/vulnerability/GHSA-vfpm-58rq-9qcg) - - - - - - 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 (), 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: - In a browser: reads your lockfile in the browser, never uploading it. - Whether it touches your code, with file and line: the Claude Code plugin, - As JSON: , or `POST https://api.agentprime.io/v1/match` with your packages () --- The web page: . Everything for agents: .