Critical
wolfssl — security advisory
If a TLS 1.3 client gets neither a PSK (pre shared key) extension nor a KSE (key share extension) when connecting to a malicious server, a default predictable buffer gets used for the IKM (Input Keying Material) value when generating the session master secret. Using a potentially known IKM value when generating the session master secret key compromises the key generated, allowing an eavesdropper to reconstruct it and potentially allowing access to or meddling with message contents in the session. This issue does not affect client validation of connected servers, nor expose private key information, but could result in an insecure TLS 1.3 session when not controlling both sides of the connection. wolfSSL recommends that TLS 1.3 client side users update the version of wolfSSL used.
- Products
- wolfssl
- Affected versions
- 3.10.2+dfsg-2, 3.12.0+dfsg-1, 3.12.2+dfsg-1, 3.13.0+dfsg-1, 3.4.8+dfsg-1, 4.1.0+dfsg-2, 4.2.0+dfsg-1, 4.2.0+dfsg-2, 4.2.0+dfsg-3, 4.3.0+dfsg-2, 4.6.0-3, 5.0.0-1, 5.1.1-1, 5.2.0-1, 5.2.0-2, 5.5.4-2, 5.5.4-2.1, 5.6.4-2, 5.6.6-1.2, 5.6.6-1.3, 5.6.6-1.3build1, 5.7.2-0.1, 5.8.2-1.2, 5.8.4-1, 5.9.1-0.1, 5.9.2-1
- Fixed versions
- Not specified
- CVEs
- CVE-2023-3724
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 01:03 UTC · Revision 1
Source evidence
If a TLS 1.3 client gets neither a PSK (pre shared key) extension nor a KSE (key share extension) when connecting to a malicious server, a default predictable buffer gets used for the IKM (Input Keying Material) value when generating the session master secret. Using a potentially known IKM value when generating the session master secret key compromises the key generated, allowing an eavesdropper to reconstruct it and potentially allowing access to or meddling with message contents in the session. This issue does not affect client validation of connected servers, nor expose private key information, but could result in an insecure TLS 1.3 session when not controlling both sides of the connection. wolfSSL recommends that TLS 1.3 client side users update the version of wolfSSL used.
osv:UBUNTU-CVE-2023-3724
wolfssl
Fixed versions: Not specified
wolfssl
Fixed versions: Not specified
wolfssl
Fixed versions: Not specified
wolfssl
Fixed versions: Not specified
wolfssl
Fixed versions: Not specified
wolfssl
Fixed versions: Not specified
wolfssl
Fixed versions: Not specified
wolfssl
Fixed versions: Not specified
Complete source record
{
"id": "33bc25f88a0220573bdc7fd8f023a0e16873bbff634b323bc5e222b677316249",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2023-3724",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "UBUNTU-CVE-2023-3724",
"summary": "If a TLS 1.3 client gets neither a PSK (pre shared key) extension nor a KSE (key share extension) when connecting to a malicious server, a default predictable buffer gets used for the IKM (Input Keying Material) value when generating the session master secret. Using a potentially known IKM value when generating the session master secret key compromises the key generated, allowing an eavesdropper to reconstruct it and potentially allowing access to or meddling with message contents in the session. This issue does not affect client validation of connected servers, nor expose private key information, but could result in an insecure TLS 1.3 session when not controlling both sides of the connection. wolfSSL recommends that TLS 1.3 client side users update the version of wolfSSL used.",
"evidence": "osv:UBUNTU-CVE-2023-3724",
"products": [
{
"name": {
"value": "wolfssl",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "3.4.8+dfsg-1",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "wolfssl",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "3.10.2+dfsg-2",
"evidence": "/affected/1/versions"
},
{
"value": "3.12.0+dfsg-1",
"evidence": "/affected/1/versions"
},
{
"value": "3.12.2+dfsg-1",
"evidence": "/affected/1/versions"
},
{
"value": "3.13.0+dfsg-1",
"evidence": "/affected/1/versions"
}
]
},
{
"name": {
"value": "wolfssl",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "4.1.0+dfsg-2",
"evidence": "/affected/2/versions"
},
{
"value": "4.2.0+dfsg-1",
"evidence": "/affected/2/versions"
},
{
"value": "4.2.0+dfsg-2",
"evidence": "/affected/2/versions"
},
{
"value": "4.2.0+dfsg-3",
"evidence": "/affected/2/versions"
},
{
"value": "4.3.0+dfsg-2",
"evidence": "/affected/2/versions"
}
]
},
{
"name": {
"value": "wolfssl",
"evidence": "/affected/3/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "4.6.0-3",
"evidence": "/affected/3/versions"
},
{
"value": "5.0.0-1",
"evidence": "/affected/3/versions"
},
{
"value": "5.1.1-1",
"evidence": "/affected/3/versions"
},
{
"value": "5.2.0-1",
"evidence": "/affected/3/versions"
},
{
"value": "5.2.0-2",
"evidence": "/affected/3/versions"
}
]
},
{
"name": {
"value": "wolfssl",
"evidence": "/affected/4/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "5.5.4-2",
"evidence": "/affected/4/versions"
},
{
"value": "5.5.4-2.1",
"evidence": "/affected/4/versions"
},
{
"value": "5.6.4-2",
"evidence": "/affected/4/versions"
},
{
"value": "5.6.6-1.2",
"evidence": "/affected/4/versions"
},
{
"value": "5.6.6-1.3",
"evidence": "/affected/4/versions"
},
{
"value": "5.6.6-1.3build1",
"evidence": "/affected/4/versions"
}
]
},
{
"name": {
"value": "wolfssl",
"evidence": "/affected/5/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "5.7.2-0.1",
"evidence": "/affected/5/versions"
}
]
},
{
"name": {
"value": "wolfssl",
"evidence": "/affected/6/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "5.9.1-0.1",
"evidence": "/affected/6/versions"
},
{
"value": "5.9.2-1",
"evidence": "/affected/6/versions"
}
]
},
{
"name": {
"value": "wolfssl",
"evidence": "/affected/7/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "5.7.2-0.1",
"evidence": "/affected/7/versions"
},
{
"value": "5.8.2-1.2",
"evidence": "/affected/7/versions"
},
{
"value": "5.8.4-1",
"evidence": "/affected/7/versions"
},
{
"value": "5.9.1-0.1",
"evidence": "/affected/7/versions"
}
]
}
],
"severity": "critical",
"structured": {
"id": "UBUNTU-CVE-2023-3724",
"aliases": [
"UBUNTU-CVE-2023-3724"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H"
},
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
},
{
"type": "Ubuntu",
"score": "medium"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "wolfssl",
"purl": "pkg:deb/ubuntu/wolfssl?arch=source&distro=xenial",
"ecosystem": "Ubuntu:16.04:LTS"
},
"versions": [
"3.4.8+dfsg-1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2023/UBUNTU-CVE-2023-3724.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libcyassl5",
"binary_version": "3.4.8+dfsg-1"
},
{
"binary_name": "libwolfssl0",
"binary_version": "3.4.8+dfsg-1"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "wolfssl",
"purl": "pkg:deb/ubuntu/wolfssl?arch=source&distro=bionic",
"ecosystem": "Ubuntu:18.04:LTS"
},
"versions": [
"3.10.2+dfsg-2",
"3.12.0+dfsg-1",
"3.12.2+dfsg-1",
"3.13.0+dfsg-1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2023/UBUNTU-CVE-2023-3724.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libwolfssl15",
"binary_version": "3.13.0+dfsg-1"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "wolfssl",
"purl": "pkg:deb/ubuntu/wolfssl?arch=source&distro=focal",
"ecosystem": "Ubuntu:20.04:LTS"
},
"versions": [
"4.1.0+dfsg-2",
"4.2.0+dfsg-1",
"4.2.0+dfsg-2",
"4.2.0+dfsg-3",
"4.3.0+dfsg-2"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2023/UBUNTU-CVE-2023-3724.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libwolfssl24",
"binary_version": "4.3.0+dfsg-2"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "wolfssl",
"purl": "pkg:deb/ubuntu/wolfssl?arch=source&distro=jammy",
"ecosystem": "Ubuntu:22.04:LTS"
},
"versions": [
"4.6.0-3",
"5.0.0-1",
"5.1.1-1",
"5.2.0-1",
"5.2.0-2"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2023/UBUNTU-CVE-2023-3724.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libwolfssl32",
"binary_version": "5.2.0-2"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "wolfssl",
"purl": "pkg:deb/ubuntu/wolfssl?arch=source&distro=noble",
"ecosystem": "Ubuntu:24.04:LTS"
},
"versions": [
"5.5.4-2",
"5.5.4-2.1",
"5.6.4-2",
"5.6.6-1.2",
"5.6.6-1.3",
"5.6.6-1.3build1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2023/UBUNTU-CVE-2023-3724.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libwolfssl42t64",
"binary_version": "5.6.6-1.3build1"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "wolfssl",
"purl": "pkg:deb/ubuntu/wolfssl?arch=source&distro=questing",
"ecosystem": "Ubuntu:25.10"
},
"versions": [
"5.7.2-0.1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2023/UBUNTU-CVE-2023-3724.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libwolfssl42t64",
"binary_version": "5.7.2-0.1"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "wolfssl",
"purl": "pkg:deb/ubuntu/wolfssl?arch=source&distro=stonking",
"ecosystem": "Ubuntu:26.10"
},
"versions": [
"5.9.1-0.1",
"5.9.2-1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2023/UBUNTU-CVE-2023-3724.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libwolfssl45",
"binary_version": "5.9.2-1"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "wolfssl",
"purl": "pkg:deb/ubuntu/wolfssl?arch=source&distro=resolute",
"ecosystem": "Ubuntu:26.04:LTS"
},
"versions": [
"5.7.2-0.1",
"5.8.2-1.2",
"5.8.4-1",
"5.9.1-0.1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2023/UBUNTU-CVE-2023-3724.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libwolfssl44",
"binary_version": "5.9.1-0.1"
}
]
}
}
],
"modified": "2026-10-17T12:56:24.185942789Z",
"provider": "osv",
"upstream": [
"CVE-2023-3724"
],
"references": [
"https://ubuntu.com/security/CVE-2023-3724",
"https://www.wolfssl.com/docs/security-vulnerabilities/",
"https://github.com/wolfSSL/wolfssl/pull/6412",
"https://www.cve.org/CVERecord?id=CVE-2023-3724"
]
},
"related_cves": [
{
"value": "CVE-2023-3724",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 355562,
"published_at": "2023-07-17T22:15:00+00:00"
}