{"id":"CVE-2020-36478","details":"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.","modified":"2026-05-18T12:02:15.898160290Z","published":"2021-08-23T02:15:07.097Z","database_specific":{"unresolved_ranges":[{"cpes":["cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*","cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*"],"vendor_product":"debian:debian_linux","source":"CPE_FIELD","extracted_events":[{"last_affected":"9.0"},{"last_affected":"10.0"}]}]},"references":[{"type":"ADVISORY","url":"https://github.com/ARMmbed/mbedtls/releases/tag/v2.16.9"},{"type":"ADVISORY","url":"https://github.com/ARMmbed/mbedtls/releases/tag/v2.25.0"},{"type":"ADVISORY","url":"https://github.com/ARMmbed/mbedtls/releases/tag/v2.7.18"},{"type":"ADVISORY","url":"https://lists.debian.org/debian-lts-announce/2021/11/msg00021.html"},{"type":"ADVISORY","url":"https://lists.debian.org/debian-lts-announce/2022/12/msg00036.html"},{"type":"FIX","url":"https://cert-portal.siemens.com/productcert/pdf/ssa-756638.pdf"},{"type":"EVIDENCE","url":"https://github.com/ARMmbed/mbedtls/issues/3629"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/Mbed-TLS/mbedtls","events":[{"introduced":"0"},{"fixed":"8254ed2a9fadede8c6bf414072f78fc78d5af61c"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"2.2"}],"cpe":["cpe:2.3:o:siemens:logo\\!_cmr2020_firmware:*:*:*:*:*:*:*:*","cpe:2.3:o:siemens:logo\\!_cmr2040_firmware:*:*:*:*:*:*:*:*"],"source":"CPE_FIELD"}}],"versions":["mbedos-techcon-oob2","mbedtls-2.1.2","mbedtls-2.1.0","mbedtls-2.1.1","beta-oob-2","mbedtls-2.0.0","polarssl-1.3.9","polarssl-1.3.8","polarssl-1.3.7","polarssl-1.3.6","polarssl-1.3.5","polarssl-1.3.4","polarssl-1.3.3","polarssl-1.3.2","polarssl-1.3.1","polarssl-1.3.0","polarssl-1.3.0-rc0","polarssl-1.2.6","polarssl-1.2.5","polarssl-1.2.4","polarssl-1.2.2","polarssl-1.2.1","polarssl-1.2.0"],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2020-36478.json"}},{"ranges":[{"type":"GIT","repo":"https://github.com/mbed-tls/mbedtls","events":[{"introduced":"0"},{"fixed":"78d9663acec4ac72af43e2db57fc73a24e856108"},{"introduced":"8be0e6db41b4a085e90cb03983f99d3a5158d450"},{"fixed":"3fac0bae4a50113989b3d015cd2d948f51a6d9ac"},{"introduced":"3f8d78411a26e833db18d9fbde0e2f0baeda87f0"},{"fixed":"1c54b5410fd48d6bcada97e30cac417c5c7eea67"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"2.7.18"},{"introduced":"2.8.0"},{"fixed":"2.16.9"},{"introduced":"2.17.0"},{"fixed":"2.25.0"}],"cpe":"cpe:2.3:a:arm:mbed_tls:*:*:*:*:*:*:*:*","source":["CPE_FIELD","REFERENCES"]}}],"versions":["v2.24.0","mbedtls-2.24.0","v2.7.17","mbedtls-2.7.17","v2.16.8","mbedtls-2.16.8","mbedtls-2.19.1","mbedtls-2.7.15","mbedtls-2.16.6","mbedtls-2.22.0d0","mbedtls-2.7.14","mbedtls-2.16.5","mbedtls-2.21.0","mbedtls-2.7.13","mbedtls-2.20.0","mbedtls-2.16.4","mbedtls-2.20.0d0","mbedtls-2.16.3","mbedtls-2.7.12","mbedtls-2.19.0d2","mbedtls-2.19.0","mbedtls-2.19.0d1","mbedtls-2.16.2","mbedtls-2.7.11","mbedtls-2.7.9","mbedtls-2.16.0","mbedtls-2.14.0","mbedtls-2.7.8","mbedtls-2.7.7","mbedtls-2.13.1","mbedtls-2.13.0","mbedtls-2.7.6","mbedtls-2.12.0","mbedtls-2.7.5","mbedtls-2.11.0","mbedtls-2.7.4","mbedtls-2.10.0","mbedtls-2.7.0","mbedtls-2.7.3","mbedtls-2.9.0","mbedtls-2.7.2","mbedtls-2.8.0","mbedtls-2.7.2-rc1","mbedtls-2.7.1","mbedtls-2.7.0-rc1","mbedtls-2.6.0","mbedtls-2.6.0-rc1","mbedtls-2.5.1","mbedtls-2.5.0","mbedtls-2.4.0","mbedtls-2.2.1","yotta-2.3.1","mbedtls-2.3.0","mbedtls-2.2.0","mbedos-release-15-11","mbedos-techcon-oob2","mbedtls-2.1.2","mbedtls-2.1.0","mbedtls-2.1.1","beta-oob-2","mbedtls-2.0.0","polarssl-1.3.9","polarssl-1.3.8","polarssl-1.3.7","polarssl-1.3.6","polarssl-1.3.5","polarssl-1.3.4","polarssl-1.3.3","polarssl-1.3.2","polarssl-1.3.1","polarssl-1.3.0","polarssl-1.3.0-rc0","polarssl-1.2.6","polarssl-1.2.5","polarssl-1.2.4","polarssl-1.2.2","polarssl-1.2.1","polarssl-1.2.0"],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2020-36478.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"}]}