GHSA-r3jv-xfgx-gj24 · Severity: critical · Ecosystem: npm — cors-anywhere vulnerable to server-side request forgery
Rob--W cors-anywhere instances configured as an open proxy allow unauthenticated external users to induce the server to make HTTP requests to arbitrary targets (SSRF). Because the proxy forwards requests and headers, an attacker can reach internal-only endpoints and link-local metadata services, retrieve instance role credentials or other sensitive metadata, and interact with internal APIs and services that are not intended to be internet-facing. The vulnerability is exploitable by sending crafted requests to the proxy with the target resource encoded in the URL; many cors-anywhere deployments forward arbitrary methods and headers (including PUT), which can permit exploitation of IMDSv2 workflows as well as access to internal management APIs. Successful exploitation can result in theft of cloud credentials, unauthorized access to internal services, remote code execution or privilege escalation (depending on reachable backends), data exfiltration, and full compromise of cloud resources. Mitigation includes: restricting the proxy to trusted origins or authentication, whitelisting allowed target hosts, preventing access to link-local and internal IP ranges, removing support for unsafe HTTP methods/headers, enabling cloud provider mitigations, and deploying network-level protections.
Conclusion & alert: CVE-2020-36851 is rated Moderate Risk (64.7/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 0.91%). Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-05-31 | 0.82% | 0.91% | +0.09% |
| 2 | 2026-05-01 | 0.89% | 0.82% | -0.06% |
| 3 | 2026-04-21 | — | 0.89% | — |
Full EPSS history (16 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 9.5 | 4.0 | CRITICAL |
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— | — | [email protected] |
GHSA-r3jv-xfgx-gj24 · Severity: critical · Ecosystem: npm — cors-anywhere vulnerable to server-side request forgery
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| No affected products in dataset. | |||