SSRF (Server-Side Request Forgery) in Umbraco CMS (CVE-2021-47776)
Summary
SSRF in Umbraco CMS (CVE-2021-47776). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
Umbraco CMS v8.14.1 contains a server-side request forgery vulnerability that allows attackers to manipulate baseUrl parameters in multiple dashboard and help controller endpoints. Attackers can craft malicious requests to the GetContextHelpForPage, GetRemoteDashboardContent, and GetRemoteDashboardCss endpoints to trigger unauthorized server-side requests to external hosts.
Source: NIST National Vulnerability Database NVD
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-2021-47776 has been found in Umbraco CMS.
Risk of unauthorized operations or information disclosure. CVSS score: 5.3/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Umbraco CMS CVE-2021-47776" on the vendor's site.
CVE-2021-47776 (Umbraco CMS) — CWE-918 / CVSS v3 5.3
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
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.
SSRF (CWE-918) exists in Umbraco CMS.
Check the vendor advisory for the affected versions of Umbraco CMS.
Severity: Medium (CVSS 5.3/10). Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
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. Audit SBOM/dependencies 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
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Umbraco CMS を使っているサービスとバージョンを洗い出す。
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2Post-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。
References
- exploit disclosure@vulncheck.com
- web disclosure@vulncheck.com
- web disclosure@vulncheck.com