High
Security advisory
DoTls13CertificateVerify in tls13.c in wolfSSL before 4.7.0 does not cease processing for certain anomalous peer behavior (sending an ED22519, ED448, ECC, or RSA signature without the corresponding certificate). The client side is affected because man-in-the-middle attackers can impersonate TLS 1.3 servers.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2021-3336
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 11:47 UTC · Revision 1
Source evidence
DoTls13CertificateVerify in tls13.c in wolfSSL before 4.7.0 does not cease processing for certain anomalous peer behavior (sending an ED22519, ED448, ECC, or RSA signature without the corresponding certificate). The client side is affected because man-in-the-middle attackers can impersonate TLS 1.3 servers.
osv:CVE-2021-3336
Complete source record
{
"id": "26f9c90f2dadc45b4ef8f02ea2bb08cbb923dc1f5a64b7613551fab7e97b8b45",
"url": "https://osv.dev/vulnerability/CVE-2021-3336",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2021-3336",
"summary": "DoTls13CertificateVerify in tls13.c in wolfSSL before 4.7.0 does not cease processing for certain anomalous peer behavior (sending an ED22519, ED448, ECC, or RSA signature without the corresponding certificate). The client side is affected because man-in-the-middle attackers can impersonate TLS 1.3 servers.",
"evidence": "osv:CVE-2021-3336",
"products": [],
"severity": "high",
"structured": {
"id": "CVE-2021-3336",
"aliases": [
"CVE-2021-3336"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/wolfssl/wolfssl",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "830de9a9fb99e30f9ac9caa0a7f7bba29c3b4863"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "4.7.0"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
"v4.6.0-stable",
"v4.5.0-stable",
"v4.4.0-stable",
"v4.3.0-stable",
"v4.2.0c",
"v4.2.0-stable",
"v4.1.0-stable",
"v4.0.0-stable",
"list",
"v3.15.7-stable",
"v3.15.6",
"v3.15.5a",
"v3.15.5-stable",
"WCv4-rng-stable",
"v3.15.3-stable",
"l",
"v3.15.0-stable",
"v3.14.4",
"v3.14.2",
"v3.14.0b",
"v3.14.0a",
"v3.14.0-stable",
"v3.13.3",
"v3.13.2",
"v3.13.0-stable",
"v3.12.2-stable",
"v3.12.0-stable",
"v3.11.1-tls13-beta",
"v3.11.0-stable",
"v3.10.3",
"v3.10.2-stable",
"v3.10.0a",
"v3.10.0-stable",
"v3.9.10b",
"v3.9.10-stable",
"v3.9.8",
"v3.9.6w",
"v3.9.6",
"v3.9.1",
"v3.9.0",
"v3.8.0",
"v3.7.3",
"v3.7.1",
"v3.7.0",
"v3.6.9",
"v3.6.8",
"v3.4.6",
"v3.4.2",
"v3.4.0",
"v3.3.3",
"v3.3.0",
"v3.2.6",
"v3.2.4",
"v3.2.0",
"v2.9.4",
"v2.9.2",
"v2.9.1",
"v0.5",
"v2.9.0",
"v2.8.6",
"v2.8.5a",
"v2.8.5",
"v2.8.4",
"v2.8.3",
"v2.8.2",
"v2.8.0",
"v2.7.2",
"v2.7.0",
"v2.6.2",
"v2.6.0",
"v2.4.7",
"v2.4.6",
"v2.4.2",
"v2.0.8",
"v2.0.6",
"v2.0.3",
"v2.0.2",
"v2.0rc3",
"v2.0rc2b",
"v2.0rc2",
"v2.0rc1",
"v1.9.0",
"v1.8.8.0"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-3336.json"
}
}
],
"modified": "2026-10-20T10:54:43.772757363Z",
"provider": "osv",
"references": [
"https://www.wolfssl.com/docs/security-vulnerabilities",
"https://github.com/wolfSSL/wolfssl/pull/3676"
],
"provider_metadata": {}
},
"related_cves": [
{
"value": "CVE-2021-3336",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 386012,
"published_at": "2021-01-29T05:15:12.197+00:00"
}