{"answers":{"affected":"2 open source packages ship an affected version, including cors-anywhere.","exploited":"There is no known exploitation of CVE-2020-36851 in the wild and no public exploit code.","fix":"Change a configuration setting.","what":"CVE-2020-36851 is a critical server-side request forgery vulnerability in Rob--W / cors-anywhere, published on 25 Sep 2025. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2020-36851 and fix it if it is affected.\n\nWhat it is: CVE-2020-36851 is a critical server-side request forgery vulnerability in Rob--W / cors-anywhere, published on 25 Sep 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2020-36851 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- cors-anywhere (npm): affected all versions up to 0.4.4; no fix listed\n- cors-anywhere (npm): affected all versions up to 0.4.4; no fix listed\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2020-36851/ (Markdown: https://insights.sbomify.com/CVE-2020-36851/index.md)","id":"CVE-2020-36851","markdown":"https://insights.sbomify.com/CVE-2020-36851/index.md","name":"CVE-2020-36851","record":{"aliases":["GHSA-r3jv-xfgx-gj24","ROOT-APP-NPM-CVE-2020-36851"],"analysis":{"component_type":"library","fix_type":"configuration_change","impacts":["data_read","privilege_escalation"],"network_reachable":"yes","non_default_config":true,"product_category":"Node.js CORS proxy","requires_auth":"none","summary":"Misconfigured CORS proxies allow attackers to perform Server-Side Request Forgery, accessing internal services and stealing cloud credentials.","user_interaction":"not_required","vuln_class":"ssrf"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"VulnCheck","cpe":[],"cvss":{"score":9.5,"severity":"critical","source":"cna","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:H","version":"4.0"},"cwes":[{"id":"CWE-942","name":"Permissive Cross-domain Security Policy with Untrusted Domains"},{"id":"CWE-918","name":"Server-Side Request Forgery"}],"description":"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.","ecosystems":["npm"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"Rob--W cors-anywhere Misconfigured CORS Proxy Allows SSRF","id":"CVE-2020-36851","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"npm","product":null,"products":[],"type":"ssrf","year":"2020"},"n_packages":2,"n_references":6,"next":{"headline":"Custom Searchable Data Entry System \u003c= 1.7.1 - Unauthenticated Database Wiping","id":"CVE-2020-36852"},"packages":[{"ecosystem":"npm","fixed":[],"introduced":["0"],"last_affected":["0.4.4"],"package":"cors-anywhere","purl":null,"source":"GHSA-r3jv-xfgx-gj24"},{"ecosystem":"npm","fixed":[],"introduced":["0"],"last_affected":["0.4.4"],"package":"cors-anywhere","purl":"pkg:npm/cors-anywhere","source":"GHSA-r3jv-xfgx-gj24"}],"prev":{"headline":"Sitecore JSS React Sample Application 11.0.0 - 14.0.1 Information Disclosure","id":"CVE-2020-36850"},"products":["Rob--W / cors-anywhere"],"published":"2025-09-25","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-10-08","vendors":["Rob--W / cors-anywhere"]},"summary":"Misconfigured CORS proxies allow attackers to perform Server-Side Request Forgery, accessing internal services and stealing cloud credentials.","url":"https://insights.sbomify.com/CVE-2020-36851/"}