{"id":"CVE-2026-77581","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-77581","generatedAt":"2026-10-28T02:21:16.338Z","title":"In 2.8.6 and earlier, the certificate and timestamp CORS proxy in cloudflare/cors-proxy-worker.js uses isPrivateOrReservedHost() to validate a supplied hostname separately from the DNS resolution used by fetch(targetUrl), allowing an attacker-controlled…","description":"BentoPDF is a client-side PDF toolkit that is self hostable. In 2.8.6 and earlier, the certificate and timestamp CORS proxy in cloudflare/cors-proxy-worker.js uses isPrivateOrReservedHost() to validate a supplied hostname separately from the DNS resolution used by fetch(targetUrl), allowing an attacker-controlled hostname to resolve to an internal or reserved destination after validation. A certificate-like path can satisfy ALLOWED_PATH_PATTERNS, and direct clients can forge the browser-oriented Origin header. Deployments without PROXY_SECRET skip the optional signature check, while the signature is an anti-abuse measure rather than a destination-security boundary. The proxy has a 10 MB response limit and can relay response bodies from reachable destinations. The advisory identifies both the official Worker deployment and self-hosted instances as impacted where the Worker execution environment can reach internal or reserved destinations. This vulnerability is fixed in 2.8.7.","published":"2026-09-24T16:17:11.000Z","lastModified":"2026-09-29T19:07:47.000Z","status":"Deferred","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":8.6,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L"},"cwe":["CWE-918"],"affected":[],"epss":{"score":0.00266,"percentile":0.18603,"date":"2026-10-26","history":[{"date":"2026-09-25","score":0.00266,"percentile":0.1675}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.27%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[{"kind":"new","label":"New CVE","at":"2026-09-24T16:17:11.000Z","detail":{"score":"8.6","severity":"HIGH","publishedAt":"2026-09-24T16:17:10.943Z"},"summary":"New CVE, high severity (CVSS 8.6)."}],"references":[{"url":"https://github.com/alam00000/bentopdf/commit/45496fcd2ed6e02dcdde0d3839cc5024c091760c","source":"security-advisories@github.com"},{"url":"https://github.com/alam00000/bentopdf/commit/58cd1a8893bfe06e4a59a72adc2e7db00a8b9266","source":"security-advisories@github.com"},{"url":"https://github.com/alam00000/bentopdf/releases/tag/v2.8.7","source":"security-advisories@github.com"},{"url":"https://github.com/alam00000/bentopdf/security/advisories/GHSA-5xjf-rr5x-pcfj","source":"security-advisories@github.com"},{"url":"https://github.com/alam00000/bentopdf/security/advisories/GHSA-5xjf-rr5x-pcfj","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-77581","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}