Vulnerability in n8n (CVE-2026-58661)
Summary
Vulnerability in n8n (CVE-2026-58661). Risk of unauthorized operations or information disclosure. Exploitable via uploadMaxFileSize. Mitigation: upgrade to 1.123.58 or later.
Original description
The description as published by the source.
Impact
An authenticated user can repeatedly upload files to the data-table upload endpoint, bypassing the per-request quota check, which does not account for files already written to the shared temporary directory. This causes temporary files to accumulate on disk until the periodic cleanup runs, potentially exhausting available disk space on the host.
Patches
Users should upgrade to the patched version once available to remediate the vulnerability.
Workarounds
If upgrading is not immediately possible, administrators should consider the following temporary mitigations:
- Restrict n8n instance access to fully trusted users only.
- Set
uploadMaxFileSizeto a low value to limit individual upload size. - Monitor and alert on disk usage in the n8n temporary upload directory.
These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.
Source: GitHub Security Advisories (Global) 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-2026-58661 has been found in n8n.
Attackers can target a specific entry point like uploadMaxFileSize over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 4.3/10.
What to do: upgrade n8n to 1.123.58 or later.
If unsure, ask your IT team or search "n8n CVE-2026-58661" on the vendor's site.
CVE-2026-58661 (n8n) — CWE-770 / CVSS v3 4.3
Attack vector: remote (network-reachable) / no user interaction
Attack surface: uploadMaxFileSize
Patched: 1.123.58 — 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-770) exists in n8n. Attackers reach the vulnerable code path via uploadMaxFileSize.
Check the vendor advisory for the affected versions of n8n. Attack surface: uploadMaxFileSize.
Severity: Medium (CVSS 4.3/10). Risk of unauthorized operations or information disclosure.
Update to 1.123.58.
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 'n8n' . 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
-
1Identify exposure identify
grep -r 'n8n' . | 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
n8n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 n8n to 1.123.58ステージング環境で 1.123.58 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
References
- advisory nvd.nist.gov
- package github.com
- web github.com
- web vulncheck.com
- web github.com
- web github.com
- web github.com
- web github.com