{"cve":"CVE-2020-36478","nvd":{"published":"2021-08-23T02:15:07.097","modified":"2026-06-17T03:15:34.697","status":"Modified","description":"An issue was discovered in Mbed TLS before 2.25.0 (and before 2.16.9 LTS and before 2.7.18 LTS). A NULL algorithm parameters entry looks identical to an array of REAL (size zero) and thus the certificate is considered valid. However, if the parameters do not match in any way, then the certificate should be considered invalid.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","score":7.5},"cwes":["CWE-295"],"references":["https://cert-portal.siemens.com/productcert/pdf/ssa-756638.pdf","https://github.com/ARMmbed/mbedtls/issues/3629","https://github.com/ARMmbed/mbedtls/releases/tag/v2.16.9","https://github.com/ARMmbed/mbedtls/releases/tag/v2.25.0","https://github.com/ARMmbed/mbedtls/releases/tag/v2.7.18"],"products":["arm:mbed_tls","debian:debian_linux","siemens:logo\\!_cmr2020_firmware","siemens:logo\\!_cmr2040_firmware","siemens:simatic_rtu3000c_firmware","siemens:simatic_rtu3030c_firmware","siemens:simatic_rtu3031c_firmware","siemens:simatic_rtu3041c_firmware"],"source":"nvd","synced_at":"2026-10-19T21:21:57.125947417+00:00"},"epss":{"cve":"CVE-2020-36478","score":0.01102,"percentile":0.65727,"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."]}