{"cve":"CVE-2020-15237","nvd":{"published":"2020-10-05T19:15:15.103","modified":"2026-06-17T02:56:19.943","status":"Modified","description":"In Shrine before version 3.3.0, when using the `derivation_endpoint` plugin, it's possible for the attacker to use a timing attack to guess the signature of the derivation URL. The problem has been fixed by comparing sent and calculated signature in constant time, using `Rack::Utils.secure_compare`. Users using the `derivation_endpoint` plugin are urged to upgrade to Shrine 3.3.0 or greater. A possible workaround is provided in the linked advisory.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","score":5.9},"cwes":["CWE-203","CWE-208"],"references":["https://github.com/shrinerb/shrine/commit/1b27090ce31543bf39f186c20ea47c8250fca2f0","https://github.com/shrinerb/shrine/security/advisories/GHSA-5jjv-x4fq-qjwp","https://github.com/shrinerb/shrine/commit/1b27090ce31543bf39f186c20ea47c8250fca2f0","https://github.com/shrinerb/shrine/security/advisories/GHSA-5jjv-x4fq-qjwp"],"products":["shrinerb:shrine"],"source":"nvd","synced_at":"2026-10-19T21:09:53.489947993+00:00"},"epss":{"cve":"CVE-2020-15237","score":0.01015,"percentile":0.63294,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-5jjv-x4fq-qjwp","url":"https://osv.dev/vulnerability/GHSA-5jjv-x4fq-qjwp","summary":"Possible timing attack in derivation_endpoint","modified":"2026-07-08T06:29:09.017617620Z","packages":[{"ecosystem":"RubyGems","name":"shrine","purl":"pkg:gem/shrine","ranges":["<3.3.0"],"fixed":["3.3.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}