nss — security advisory
During RSA key generation, bignum implementations used a variation of the Binary Extended Euclidean Algorithm which entailed significantly input-dependent flow. This allowed an attacker able to perform electromagnetic-based side channel attacks to record traces leading to the recovery of the secret primes. *Note:* An unmodified Firefox browser does not generate RSA keys in normal operation and is not affected, but products built on top of it might. This vulnerability affects Firefox < 78.
- Products
- nss
- Affected versions
- Not specified
- Fixed versions
- 2:3.53.1-1
- CVEs
- CVE-2020-12402
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 12:31 UTC · Revision 1
Source evidence
During RSA key generation, bignum implementations used a variation of the Binary Extended Euclidean Algorithm which entailed significantly input-dependent flow. This allowed an attacker able to perform electromagnetic-based side channel attacks to record traces leading to the recovery of the secret primes. *Note:* An unmodified Firefox browser does not generate RSA keys in normal operation and is not affected, but products built on top of it might. This vulnerability affects Firefox < 78.
osv:DEBIAN-CVE-2020-12402
nss
Fixed versions: 2:3.53.1-1
nss
Fixed versions: 2:3.53.1-1
nss
Fixed versions: 2:3.53.1-1
Complete source record
{
"id": "3af06e31fb555644439f754fda2aedfeac9e257cf264d0b04045ae907fb21574",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2020-12402",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2020-12402",
"summary": "During RSA key generation, bignum implementations used a variation of the Binary Extended Euclidean Algorithm which entailed significantly input-dependent flow. This allowed an attacker able to perform electromagnetic-based side channel attacks to record traces leading to the recovery of the secret primes. *Note:* An unmodified Firefox browser does not generate RSA keys in normal operation and is not affected, but products built on top of it might. This vulnerability affects Firefox < 78.",
"evidence": "osv:DEBIAN-CVE-2020-12402",
"products": [
{
"name": {
"value": "nss",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2:3.53.1-1",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "nss",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2:3.53.1-1",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "nss",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2:3.53.1-1",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": []
}
],
"severity": "medium",
"structured": {
"id": "DEBIAN-CVE-2020-12402",
"aliases": [
"DEBIAN-CVE-2020-12402"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:N/A:N"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2:3.53.1-1"
}
]
}
],
"package": {
"name": "nss",
"purl": "pkg:deb/debian/nss?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2020-12402.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2:3.53.1-1"
}
]
}
],
"package": {
"name": "nss",
"purl": "pkg:deb/debian/nss?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2020-12402.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2:3.53.1-1"
}
]
}
],
"package": {
"name": "nss",
"purl": "pkg:deb/debian/nss?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2020-12402.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-26T12:00:27.521499229Z",
"provider": "osv",
"upstream": [
"CVE-2020-12402"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2020-12402"
]
},
"related_cves": [
{
"value": "CVE-2020-12402",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 451132,
"published_at": "2020-07-09T15:15:10.82+00:00"
}