mbedtls — security advisory
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.
- Products
- mbedtls
- Affected versions
- Not specified
- Fixed versions
- 2.16.9-0.1
- CVEs
- CVE-2020-10932
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 12:55 UTC · Revision 1
Source evidence
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.
osv:DEBIAN-CVE-2020-10932
mbedtls
Fixed versions: 2.16.9-0.1
mbedtls
Fixed versions: 2.16.9-0.1
mbedtls
Fixed versions: 2.16.9-0.1
Complete source record
{
"id": "ba4dee12b224c4d2255648e2f569723b3affb2d411032c495ef5cb2a12219523",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2020-10932",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2020-10932",
"summary": "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.",
"evidence": "osv:DEBIAN-CVE-2020-10932",
"products": [
{
"name": {
"value": "mbedtls",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
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"evidence": "/affected/0/ranges"
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"affected_versions": []
},
{
"name": {
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{
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"severity": "medium",
"structured": {
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"aliases": [
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"metrics": [
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"type": "CVSS_V3",
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}
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"affected": [
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"package": {
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"ecosystem": "Debian:12"
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"database_specific": {
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{
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"package": {
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"purl": "pkg:deb/debian/mbedtls?arch=source&distro=trixie",
"ecosystem": "Debian:13"
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"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2020-10932.json"
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{
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"package": {
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"purl": "pkg:deb/debian/mbedtls?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2020-10932.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-26T12:01:17.077012960Z",
"provider": "osv",
"upstream": [
"CVE-2020-10932"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2020-10932"
]
},
"related_cves": [
{
"value": "CVE-2020-10932",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 451541,
"published_at": "2020-04-15T14:15:20.123+00:00"
}