{"cve":"CVE-2017-3737","nvd":{"published":"2017-12-07T16:29:00.193","modified":"2026-06-17T01:18:49.363","status":"Modified","description":"OpenSSL 1.0.2 (starting from version 1.0.2b) introduced an \"error state\" mechanism. The intent was that if a fatal error occurred during a handshake then OpenSSL would move into the error state and would immediately fail if you attempted to continue the handshake. This works as designed for the explicit handshake functions (SSL_do_handshake(), SSL_accept() and SSL_connect()), however due to a bug it does not work correctly if SSL_read() or SSL_write() is called directly. In that scenario, if the handshake fails then a fatal error will be returned in the initial function call. If SSL_read()/SSL_write() is subsequently called by the application for the same SSL object then it will succeed and the data is passed without being decrypted/encrypted directly from the SSL/TLS record layer. In order to exploit this issue an application bug would have to be present that resulted in a call to SSL_read()/SSL_write() being issued after having already received a fatal error. OpenSSL version 1.0.2b-1.0.2m are affected. Fixed in OpenSSL 1.0.2n. OpenSSL 1.1.0 is not affected.","cvss_v4":null,"cvss_v3":{"version":"3.0","vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","score":5.9},"cwes":["CWE-125","CWE-787"],"references":["http://www.oracle.com/technetwork/security-advisory/cpuapr2018-3678067.html","http://www.oracle.com/technetwork/security-advisory/cpujan2018-3236628.html","http://www.oracle.com/technetwork/security-advisory/cpujul2018-4258247.html","http://www.securityfocus.com/bid/102103","http://www.securitytracker.com/id/1039978"],"products":["debian:debian_linux","openssl:openssl"],"source":"nvd","synced_at":"2026-10-19T20:47:56.471723566+00:00"},"epss":{"cve":"CVE-2017-3737","score":0.78675,"percentile":0.99588,"date":"2026-10-31"},"kev":null,"osv":[],"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."]}