{"id":"UBUNTU-CVE-2020-10932","details":"An issue was discovered in Arm Mbed TLS before 2.16.6 and 2.7.x before 2.7.15. An attacker that can get precise enough side-channel measurements can recover the long-term ECDSA private key by (1) reconstructing the projective coordinate of the result of scalar multiplication by exploiting side channels in the conversion to affine coordinates; (2) using an attack described by Naccache, Smart, and Stern in 2003 to recover a few bits of the ephemeral scalar from those projective coordinates via several measurements; and (3) using a lattice attack to get from there to the long-term ECDSA private key used for the signatures. Typically an attacker would have sufficient access when attacking an SGX enclave and controlling the untrusted OS.","modified":"2026-04-22T13:57:33.198460Z","published":"2020-04-15T14:15:00Z","upstream":["CVE-2020-10932"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2020-10932"},{"type":"REPORT","url":"https://tls.mbed.org/tech-updates/releases/mbedtls-2.16.6-and-2.7.15-released"},{"type":"REPORT","url":"https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security-advisory-2020-04"},{"type":"REPORT","url":"https://tls.mbed.org/tech-updates/security-advisories"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2020-10932"}],"affected":[{"package":{"name":"mbedtls","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/mbedtls@2.2.1-2ubuntu0.3?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.1.2-1","2.2.0-1","2.2.1-1","2.2.1-2","2.2.1-2ubuntu0.1","2.2.1-2ubuntu0.2","2.2.1-2ubuntu0.3"],"ecosystem_specific":{"binaries":[{"binary_name":"libmbedcrypto0","binary_version":"2.2.1-2ubuntu0.3"},{"binary_name":"libmbedtls10","binary_version":"2.2.1-2ubuntu0.3"},{"binary_name":"libmbedx509-0","binary_version":"2.2.1-2ubuntu0.3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2020/UBUNTU-CVE-2020-10932.json"}},{"package":{"name":"mbedtls","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/mbedtls@2.8.0-1ubuntu0.1~esm1?arch=source&distro=esm-apps/bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.5.1-1ubuntu1","2.6.0-1","2.7.0-2","2.8.0-1","2.8.0-1ubuntu0.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"libmbedcrypto1","binary_version":"2.8.0-1ubuntu0.1~esm1"},{"binary_name":"libmbedtls10","binary_version":"2.8.0-1ubuntu0.1~esm1"},{"binary_name":"libmbedx509-0","binary_version":"2.8.0-1ubuntu0.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2020/UBUNTU-CVE-2020-10932.json"}},{"package":{"name":"mbedtls","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/mbedtls@2.16.4-1ubuntu2+esm1?arch=source&distro=esm-apps/focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.16.2-1","2.16.3-1","2.16.4-1ubuntu2","2.16.4-1ubuntu2+esm1"],"ecosystem_specific":{"binaries":[{"binary_version":"2.16.4-1ubuntu2+esm1","binary_name":"libmbedcrypto3"},{"binary_name":"libmbedtls12","binary_version":"2.16.4-1ubuntu2+esm1"},{"binary_name":"libmbedx509-0","binary_version":"2.16.4-1ubuntu2+esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2020/UBUNTU-CVE-2020-10932.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N"},{"type":"Ubuntu","score":"medium"}]}