ubuntu-cve-2026-56822
Vulnerability from osv_ubuntu
Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.136.Final and 4.2.16.Final, the OcspServerCertificateValidator forwards the SslHandshakeCompletionEvent before the asynchronous OCSP validation completes. This allows the client's downstream handlers to send sensitive application data (e.g., HTTP requests) to a revoked server before the channel is closed by the OCSP check. n io.netty.handler.ssl.ocsp.OcspServerCertificateValidator#userEventTriggered, when an SslHandshakeCompletionEvent is received, the validator immediately calls ctx.fireUserEventTriggered(evt). It then initiates an asynchronous OCSP query using OcspClient.query. Because the handshake completion event is forwarded immediately, downstream handlers in the client's pipeline are notified that the TLS handshake is successful. They may then begin reading and processing incoming application data or sending outgoing data. If the OCSP response later indicates the server's certificate is REVOKED, the validator closes the channel, but by this time, the client may have already leaked sensitive data to a revoked server or processed malicious responses from it. This issue has been fixed in versions 4.1.136.Final and 4.2.16.Final.
{
"affected": [
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libnetty-java",
"binary_version": "1:3.2.6.Final-2+deb8u2ubuntu0.1~esm1"
}
]
},
"package": {
"ecosystem": "Ubuntu:Pro:14.04:LTS",
"name": "netty",
"purl": "pkg:deb/ubuntu/netty@1:3.2.6.Final-2+deb8u2ubuntu0.1~esm1?arch=source\u0026distro=esm-infra-legacy/trusty"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"1:3.2.6.Final-2",
"1:3.2.6.Final-2+deb8u2build0.14.04.1~esm1",
"1:3.2.6.Final-2+deb8u2ubuntu0.1~esm1"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libnetty-java",
"binary_version": "1:4.0.34-1ubuntu0.1~esm4"
}
]
},
"package": {
"ecosystem": "Ubuntu:Pro:16.04:LTS",
"name": "netty",
"purl": "pkg:deb/ubuntu/netty@1:4.0.34-1ubuntu0.1~esm4?arch=source\u0026distro=esm-apps-legacy/xenial"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"1:3.2.6.Final-2",
"1:4.0.32-1",
"1:4.0.33-1",
"1:4.0.34-1",
"1:4.0.34-1ubuntu0.1~esm1",
"1:4.0.34-1ubuntu0.1~esm2",
"1:4.0.34-1ubuntu0.1~esm3",
"1:4.0.34-1ubuntu0.1~esm4"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libnetty-java",
"binary_version": "1:4.1.7-4ubuntu0.1+esm6"
}
]
},
"package": {
"ecosystem": "Ubuntu:Pro:18.04:LTS",
"name": "netty",
"purl": "pkg:deb/ubuntu/netty@1:4.1.7-4ubuntu0.1+esm6?arch=source\u0026distro=esm-apps/bionic"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"1:4.1.7-4",
"1:4.1.7-4ubuntu0.1~esm1",
"1:4.1.7-4ubuntu0.1",
"1:4.1.7-4ubuntu0.1+esm1",
"1:4.1.7-4ubuntu0.1+esm2",
"1:4.1.7-4ubuntu0.1+esm3",
"1:4.1.7-4ubuntu0.1+esm4",
"1:4.1.7-4ubuntu0.1+esm5",
"1:4.1.7-4ubuntu0.1+esm6"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libnetty-java",
"binary_version": "1:4.1.45-1ubuntu0.1~esm6"
}
]
},
"package": {
"ecosystem": "Ubuntu:Pro:20.04:LTS",
"name": "netty",
"purl": "pkg:deb/ubuntu/netty@1:4.1.45-1ubuntu0.1~esm6?arch=source\u0026distro=esm-apps/focal"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"1:4.1.33-1",
"1:4.1.33-2",
"1:4.1.33-3",
"1:4.1.45-1",
"1:4.1.45-1ubuntu0.1~esm1",
"1:4.1.45-1ubuntu0.1~esm2",
"1:4.1.45-1ubuntu0.1~esm3",
"1:4.1.45-1ubuntu0.1~esm4",
"1:4.1.45-1ubuntu0.1~esm6"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libnetty-java",
"binary_version": "1:4.1.48-4+deb11u2ubuntu0.1+esm3"
}
]
},
"package": {
"ecosystem": "Ubuntu:Pro:22.04:LTS",
"name": "netty",
"purl": "pkg:deb/ubuntu/netty@1:4.1.48-4+deb11u2ubuntu0.1+esm3?arch=source\u0026distro=esm-apps/jammy"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"1:4.1.48-4",
"1:4.1.48-4+deb11u1build0.22.04.1",
"1:4.1.48-4+deb11u2build0.22.04.1",
"1:4.1.48-4+deb11u2ubuntu0.1~esm1",
"1:4.1.48-4+deb11u2ubuntu0.1~esm2",
"1:4.1.48-4+deb11u2ubuntu0.1",
"1:4.1.48-4+deb11u2ubuntu0.1+esm1",
"1:4.1.48-4+deb11u2ubuntu0.1+esm3"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libnetty-java",
"binary_version": "1:4.1.48-9ubuntu0.1+esm3"
}
]
},
"package": {
"ecosystem": "Ubuntu:Pro:24.04:LTS",
"name": "netty",
"purl": "pkg:deb/ubuntu/netty@1:4.1.48-9ubuntu0.1+esm3?arch=source\u0026distro=esm-apps/noble"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"1:4.1.48-7",
"1:4.1.48-8",
"1:4.1.48-9",
"1:4.1.48-9ubuntu0.1~esm1",
"1:4.1.48-9ubuntu0.1~esm2",
"1:4.1.48-9ubuntu0.1",
"1:4.1.48-9ubuntu0.1+esm1",
"1:4.1.48-9ubuntu0.1+esm3"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libnetty-buffer-java",
"binary_version": "1:4.1.48-16ubuntu0.1~esm2"
},
{
"binary_name": "libnetty-common-java",
"binary_version": "1:4.1.48-16ubuntu0.1~esm2"
},
{
"binary_name": "libnetty-java",
"binary_version": "1:4.1.48-16ubuntu0.1~esm2"
}
]
},
"package": {
"ecosystem": "Ubuntu:Pro:26.04:LTS",
"name": "netty",
"purl": "pkg:deb/ubuntu/netty@1:4.1.48-16ubuntu0.1~esm2?arch=source\u0026distro=esm-apps/resolute"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"1:4.1.48-10",
"1:4.1.48-11",
"1:4.1.48-12",
"1:4.1.48-13",
"1:4.1.48-14",
"1:4.1.48-16",
"1:4.1.48-16ubuntu0.1~esm2"
]
}
],
"aliases": [],
"details": "Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.136.Final and 4.2.16.Final, the OcspServerCertificateValidator forwards the SslHandshakeCompletionEvent before the asynchronous OCSP validation completes. This allows the client\u0027s downstream handlers to send sensitive application data (e.g., HTTP requests) to a revoked server before the channel is closed by the OCSP check. n io.netty.handler.ssl.ocsp.OcspServerCertificateValidator#userEventTriggered, when an SslHandshakeCompletionEvent is received, the validator immediately calls ctx.fireUserEventTriggered(evt). It then initiates an asynchronous OCSP query using OcspClient.query. Because the handshake completion event is forwarded immediately, downstream handlers in the client\u0027s pipeline are notified that the TLS handshake is successful. They may then begin reading and processing incoming application data or sending outgoing data. If the OCSP response later indicates the server\u0027s certificate is REVOKED, the validator closes the channel, but by this time, the client may have already leaked sensitive data to a revoked server or processed malicious responses from it. This issue has been fixed in versions 4.1.136.Final and 4.2.16.Final.",
"id": "UBUNTU-CVE-2026-56822",
"modified": "2026-08-06T00:20:55Z",
"published": "2026-07-29T00:16:00Z",
"references": [
{
"type": "REPORT",
"url": "https://ubuntu.com/security/CVE-2026-56822"
},
{
"type": "REPORT",
"url": "https://www.cve.org/CVERecord?id=CVE-2026-56822"
},
{
"type": "REPORT",
"url": "https://github.com/netty/netty/security/advisories/GHSA-wc96-39fc-566f"
}
],
"related": [],
"schema_version": "1.7.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
"type": "CVSS_V3"
},
{
"score": "medium",
"type": "Ubuntu"
}
],
"upstream": [
"CVE-2026-56822"
]
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.