Vulnerability in parse-nested-form-data (CVE-2026-45302)
Summary
Vulnerability in parse-nested-form-data (CVE-2026-45302). Data can be tampered with by attackers. Exploitable via __proto__. Mitigation: upgrade to 1.0.1 or later.
Original description
The description as published by the source.
parse-nested-form-data is a tiny node module for parsing FormData by name into objects and arrays. Prior to version 1.0.1, parseFormData() walks bracket and dot-notation FormData field names into nested objects without filtering reserved property keys. A single FormData field whose name begins with proto, or contains .proto. mid-path, causes the parser to traverse onto Object.prototype and assign properties there, polluting the prototype chain of every plain object in the running process. This issue has been patched in version 1.0.1.
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-2026-45302 has been found in parse-nested-form-data.
Attackers can target a specific entry point like __proto__ over the network to misuse the product.
Data can be tampered with by attackers. CVSS score: 8.2/10.
What to do: upgrade parse-nested-form-data to 1.0.1 or later.
If unsure, ask your IT team or search "parse-nested-form-data CVE-2026-45302" on the vendor's site.
CVE-2026-45302 (parse-nested-form-data) — CWE-1321 / CVSS v3 8.2
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: __proto__ / Object.prototype / handlePathPart / constructor.prototype.x
Patched: 1.0.1 — 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-1321) exists in parse-nested-form-data. Attackers reach the vulnerable code path via __proto__ without authentication.
Check the vendor advisory for the affected versions of parse-nested-form-data. Attack surface: __proto__ / Object.prototype / handlePathPart / constructor.prototype.x.
Severity: High (CVSS 8.2/10). Data can be tampered with by attackers.
Update to 1.0.1.
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 'parse-nested-form-data' . 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 'parse-nested-form-data' . | 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
parse-nested-form-data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 parse-nested-form-data to 1.0.1ステージング環境で 1.0.1 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
References
- advisory github.com
- advisory nvd.nist.gov
- advisory github.com
- package github.com
- patch github.com
- web github.com
- web github.com