Medium
wolfssl — security advisory
Improper Input Validation in the TLS 1.3 CKS extension parsing in wolfSSL 5.8.2 and earlier on multiple platforms allows a remote unauthenticated attacker to potentially cause a denial-of-service via a crafted ClientHello message with duplicate CKS extensions.
- Products
- wolfssl
- Affected versions
- 5.5.4-2, 5.5.4-2+deb12u1, 5.5.4-2+deb12u2, 5.5.4-2+deb12u3, 5.5.4-2.1, 5.6.4-1, 5.6.4-2, 5.6.6-1, 5.6.6-1.1, 5.6.6-1.2, 5.6.6-1.3, 5.6.6-1.3~exp1, 5.7.0-0.1, 5.7.0-0.2, 5.7.0-0.3, 5.7.2-0.1, 5.7.2-0.1+deb13u1, 5.7.2-0.1+deb13u2, 5.7.2-0.2, 5.7.2-0.3, 5.7.2-0.4, 5.8.2-1, 5.8.2-1.1, 5.8.2-1.2, 5.8.4-1, 5.9.0-0.1, 5.9.0-0.2, 5.9.1-0.1, 5.9.2-1
- Fixed versions
- Not specified
- CVEs
- CVE-2025-11933
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 28 Oct 2026, 11:06 UTC · Revision 1
Source evidence
Improper Input Validation in the TLS 1.3 CKS extension parsing in wolfSSL 5.8.2 and earlier on multiple platforms allows a remote unauthenticated attacker to potentially cause a denial-of-service via a crafted ClientHello message with duplicate CKS extensions.
osv:DEBIAN-CVE-2025-11933
wolfssl
Fixed versions: Not specified
wolfssl
Fixed versions: Not specified
Complete source record
{
"id": "2e01fb89f3047f079404dd661945d6f45b11ddf2d4d4d3284f322327aea5f39e",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2025-11933",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2025-11933",
"summary": "Improper Input Validation in the TLS 1.3 CKS extension parsing in wolfSSL 5.8.2 and earlier on multiple platforms allows a remote unauthenticated attacker to potentially cause a denial-of-service via a crafted ClientHello message with duplicate CKS extensions.",
"evidence": "osv:DEBIAN-CVE-2025-11933",
"products": [
{
"name": {
"value": "wolfssl",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "5.5.4-2",
"evidence": "/affected/0/versions"
},
{
"value": "5.5.4-2+deb12u1",
"evidence": "/affected/0/versions"
},
{
"value": "5.5.4-2+deb12u2",
"evidence": "/affected/0/versions"
},
{
"value": "5.5.4-2+deb12u3",
"evidence": "/affected/0/versions"
},
{
"value": "5.5.4-2.1",
"evidence": "/affected/0/versions"
},
{
"value": "5.6.4-1",
"evidence": "/affected/0/versions"
},
{
"value": "5.6.4-2",
"evidence": "/affected/0/versions"
},
{
"value": "5.6.6-1",
"evidence": "/affected/0/versions"
},
{
"value": "5.6.6-1.1",
"evidence": "/affected/0/versions"
},
{
"value": "5.6.6-1.2",
"evidence": "/affected/0/versions"
},
{
"value": "5.6.6-1.3",
"evidence": "/affected/0/versions"
},
{
"value": "5.6.6-1.3~exp1",
"evidence": "/affected/0/versions"
},
{
"value": "5.7.0-0.1",
"evidence": "/affected/0/versions"
},
{
"value": "5.7.0-0.2",
"evidence": "/affected/0/versions"
},
{
"value": "5.7.0-0.3",
"evidence": "/affected/0/versions"
},
{
"value": "5.7.2-0.1",
"evidence": "/affected/0/versions"
},
{
"value": "5.7.2-0.2",
"evidence": "/affected/0/versions"
},
{
"value": "5.7.2-0.3",
"evidence": "/affected/0/versions"
},
{
"value": "5.7.2-0.4",
"evidence": "/affected/0/versions"
},
{
"value": "5.8.2-1",
"evidence": "/affected/0/versions"
},
{
"value": "5.8.2-1.1",
"evidence": "/affected/0/versions"
},
{
"value": "5.8.2-1.2",
"evidence": "/affected/0/versions"
},
{
"value": "5.8.4-1",
"evidence": "/affected/0/versions"
},
{
"value": "5.9.0-0.1",
"evidence": "/affected/0/versions"
},
{
"value": "5.9.0-0.2",
"evidence": "/affected/0/versions"
},
{
"value": "5.9.1-0.1",
"evidence": "/affected/0/versions"
},
{
"value": "5.9.2-1",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "wolfssl",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "5.7.2-0.1",
"evidence": "/affected/1/versions"
},
{
"value": "5.7.2-0.1+deb13u1",
"evidence": "/affected/1/versions"
},
{
"value": "5.7.2-0.1+deb13u2",
"evidence": "/affected/1/versions"
},
{
"value": "5.7.2-0.2",
"evidence": "/affected/1/versions"
},
{
"value": "5.7.2-0.3",
"evidence": "/affected/1/versions"
},
{
"value": "5.7.2-0.4",
"evidence": "/affected/1/versions"
},
{
"value": "5.8.2-1",
"evidence": "/affected/1/versions"
},
{
"value": "5.8.2-1.1",
"evidence": "/affected/1/versions"
},
{
"value": "5.8.2-1.2",
"evidence": "/affected/1/versions"
},
{
"value": "5.8.4-1",
"evidence": "/affected/1/versions"
},
{
"value": "5.9.0-0.1",
"evidence": "/affected/1/versions"
},
{
"value": "5.9.0-0.2",
"evidence": "/affected/1/versions"
},
{
"value": "5.9.1-0.1",
"evidence": "/affected/1/versions"
},
{
"value": "5.9.2-1",
"evidence": "/affected/1/versions"
}
]
}
],
"severity": "medium",
"structured": {
"id": "DEBIAN-CVE-2025-11933",
"aliases": [
"DEBIAN-CVE-2025-11933"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "wolfssl",
"purl": "pkg:deb/debian/wolfssl?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"5.5.4-2",
"5.5.4-2+deb12u1",
"5.5.4-2+deb12u2",
"5.5.4-2+deb12u3",
"5.5.4-2.1",
"5.6.4-1",
"5.6.4-2",
"5.6.6-1",
"5.6.6-1.1",
"5.6.6-1.2",
"5.6.6-1.3",
"5.6.6-1.3~exp1",
"5.7.0-0.1",
"5.7.0-0.2",
"5.7.0-0.3",
"5.7.2-0.1",
"5.7.2-0.2",
"5.7.2-0.3",
"5.7.2-0.4",
"5.8.2-1",
"5.8.2-1.1",
"5.8.2-1.2",
"5.8.4-1",
"5.9.0-0.1",
"5.9.0-0.2",
"5.9.1-0.1",
"5.9.2-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-11933.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "wolfssl",
"purl": "pkg:deb/debian/wolfssl?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"5.7.2-0.1",
"5.7.2-0.1+deb13u1",
"5.7.2-0.1+deb13u2",
"5.7.2-0.2",
"5.7.2-0.3",
"5.7.2-0.4",
"5.8.2-1",
"5.8.2-1.1",
"5.8.2-1.2",
"5.8.4-1",
"5.9.0-0.1",
"5.9.0-0.2",
"5.9.1-0.1",
"5.9.2-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-11933.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-09T09:47:22.887364951Z",
"provider": "osv",
"upstream": [
"CVE-2025-11933"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2025-11933"
]
},
"related_cves": [
{
"value": "CVE-2025-11933",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 111418,
"published_at": "2025-11-21T23:15:44.293+00:00"
}