BentoPDF is a privacy-focused PDF toolkit that runs in the browser. In versions through 2.8.6, cloudflare/cors-proxy-worker.js performs a DNS-over-HTTPS safety check in hostnameResolvesToPrivate(), as used by isValidCertificateUrl() and isValidTsaUrl(), separately from the outbound fetch(targetUrl, ...). In deployments where PROXY_SECRET validation is not enabled, a direct client that controls authoritative DNS can forge the Origin header, supply a certificate, OCSP, CRL, or TSA URL that passes the proxy's accepted path checks, return a public address during validation, and return a private or link-local address during the later fetch. The endpoint can return allowed response bodies to the attacker, but exploitation requires precise timing, redirects and IP-literal obfuscation are blocked, and network reachability limits the target. This vulnerability is fixed in 2.8.7.
History

Sat, 17 Oct 2026 02:30:00 +0000

Type Values Removed Values Added
First Time appeared Alam00000
Alam00000 bentopdf
Vendors & Products Alam00000
Alam00000 bentopdf

Thu, 15 Oct 2026 17:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Wed, 14 Oct 2026 19:15:00 +0000

Type Values Removed Values Added
Description BentoPDF is a privacy-focused PDF toolkit that runs in the browser. In versions through 2.8.6, cloudflare/cors-proxy-worker.js performs a DNS-over-HTTPS safety check in hostnameResolvesToPrivate(), as used by isValidCertificateUrl() and isValidTsaUrl(), separately from the outbound fetch(targetUrl, ...). In deployments where PROXY_SECRET validation is not enabled, a direct client that controls authoritative DNS can forge the Origin header, supply a certificate, OCSP, CRL, or TSA URL that passes the proxy's accepted path checks, return a public address during validation, and return a private or link-local address during the later fetch. The endpoint can return allowed response bodies to the attacker, but exploitation requires precise timing, redirects and IP-literal obfuscation are blocked, and network reachability limits the target. This vulnerability is fixed in 2.8.7.
Title BentoPDF: SSRF via DNS Rebinding (TOCTOU) in Cloudflare CORS Proxy Worker
Weaknesses CWE-367
CWE-918
References
Metrics cvssV3_1

{'score': 6.8, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2026-10-14T19:00:13.518Z

Updated: 2026-10-15T16:19:56.322Z

Reserved: 2026-09-28T22:38:42.255Z

Link: CVE-2026-102354

cve-icon Vulnrichment

Updated: 2026-10-15T16:19:53.119Z

cve-icon NVD

Status : Deferred

Published: 2026-10-14T19:17:04.877

Modified: 2026-10-15T17:17:08.797

Link: CVE-2026-102354

cve-icon Redhat

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