Vulnerability in wasmtime-wasi (CVE-2026-58494)
Summary
Vulnerability in wasmtime-wasi (CVE-2026-58494). Data can be tampered with by attackers. Exploitable via WasiCtxBuilder. Mitigation: upgrade to 24.0.11, 36.0.12, 45.0.3, 46.0.1 or later.
Original description
The description as published by the source.
Wasmtime is a runtime for WebAssembly. Prior to 24.0.11, 36.0.12, 45.0.3, and 46.0.1, wasmtime-wasi hard-link creation and renaming check directory permissions but not matching FilePerms on source and destination preopens, allowing a WASI guest with a read-only source file capability to overwrite host files exposed as FilePerms::READ through wasip1, wasip2, or wasip3 filesystem interfaces. This issue is fixed in versions 24.0.11, 36.0.12, 45.0.3, and 46.0.1.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-58494 has been found in wasmtime-wasi.
Attackers can target a specific entry point like WasiCtxBuilder over the network to misuse the product.
Data can be tampered with by attackers. CVSS score: 6.5/10.
What to do: upgrade wasmtime-wasi to 24.0.11, 36.0.12, 45.0.3, 46.0.1 or later.
If unsure, ask your IT team or search "wasmtime-wasi CVE-2026-58494" on the vendor's site.
CVE-2026-58494 (wasmtime-wasi) — CWE-281 / CVSS v3 6.5
Attack vector: local / no user interaction
Attack surface: WasiCtxBuilder / FilePerms / file_perms / target
Patched: 24.0.11, 36.0.12, 45.0.3, 46.0.1 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-281) exists in wasmtime-wasi. Attackers reach the vulnerable code path via WasiCtxBuilder.
Check the vendor advisory for the affected versions of wasmtime-wasi. Attack surface: WasiCtxBuilder / FilePerms / file_perms / target.
Severity: Medium (CVSS 6.5/10). Data can be tampered with by attackers.
Update to 24.0.11, 36.0.12, 45.0.3, 46.0.1.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'wasmtime-wasi' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
grep -r 'wasmtime-wasi' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
wasmtime-wasiを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade wasmtime-wasi to 24.0.11, 36.0.12, 45.0.3, 46.0.1ステージング環境で 24.0.11, 36.0.12, 45.0.3, 46.0.1 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-58494 rust-wasmtime
- Ubuntu UBUNTU-CVE-2026-58494 rust-wasmtime
References
- advisory github.com
- advisory nvd.nist.gov
- advisory github.com
- package crates.io
- package github.com
- patch github.com
- patch github.com
- patch github.com
- patch github.com
- web github.com
- web github.com
- web github.com
- web github.com
- web rustsec.org
- web github.com
- web github.com