Unrestricted File Upload in parse-server (CVE-2026-55778)
Summary
Vulnerability in parse-server (CVE-2026-55778). Risk of unauthorized operations or information disclosure. Exploitable via fileUpload.fileExtensions. Mitigation: upgrade to 8.6.81 or later.
Original description
The description as published by the source.
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 9.9.1-alpha.11 and 8.6.81, the default fileUpload.fileExtensions blocklist could be bypassed by uploading a file with a non-standard or compound extension and dangerous content type, allowing storage adapters such as S3 and GCS to serve attacker-supplied active content and enable stored cross-site scripting. This issue is fixed in versions 9.9.1-alpha.11 and 8.6.81.
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-2026-55778 has been found in parse-server.
Attackers can target a specific entry point like fileUpload.fileExtensions over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: upgrade parse-server to 8.6.81 or later.
If unsure, ask your IT team or search "parse-server CVE-2026-55778" on the vendor's site.
CVE-2026-55778 (parse-server) — CWE-434
Attack surface: fileUpload.fileExtensions
Patched: 8.6.81 — apply immediately
Workaround: Configure fileUpload.fileExtensions as a strict allowlist of only the file extensions your application needs (for example ["^(png|jpe?g|gif|pdf)$"]) instead of relying on the default blocklist.
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-434) exists in parse-server. Attackers reach the vulnerable code path via fileUpload.fileExtensions.
Check the vendor advisory for the affected versions of parse-server. Attack surface: fileUpload.fileExtensions.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 8.6.81.
Workaround: Configure fileUpload.fileExtensions as a strict allowlist of only the file extensions your application needs (for example ["^(png|jpe?g|gif|pdf)$"]) instead of relying on the default blocklist.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'parse-server' . 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 'parse-server' . | 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-serverを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply temporary workaround mitigate
Configure `fileUpload.fileExtensions` as a strict allowlist of only the file extensions your application needs (for example `["^(png|jpe?g|gif|pdf)$"]`) instead of relying on the default blocklist.パッチが適用されるまでの応急処置として、Configure
fileUpload.fileExtensionsas a strict allowlist of only the file extensions your application needs (for example["^(png|jpe?g|gif|pdf)$"]) instead of relying on the default blocklist. を実施。回避策の副作用 (機能低下) を確認した上で。 -
3Apply patch patch
Upgrade parse-server to 8.6.81ステージング環境で 8.6.81 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。
-
4Post-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
- patch github.com
- patch github.com
- patch github.com
- web github.com
- web github.com
- web github.com