ubuntu-cve-2026-34479
Vulnerability from osv_ubuntu
Published
2026-04-10 16:16
Modified
2026-05-20 15:27
Summary
Details
The Log4j1XmlLayout from the Apache Log4j 1-to-Log4j 2 bridge fails to escape characters forbidden by the XML 1.0 standard, producing malformed XML output. Conforming XML parsers are required to reject documents containing such characters with a fatal error, which may cause downstream log processing systems to drop or fail to index affected records. Two groups of users are affected: * Those using Log4j1XmlLayout directly in a Log4j Core 2 configuration file. * Those using the Log4j 1 configuration compatibility layer with org.apache.log4j.xml.XMLLayout specified as the layout class. Users are advised to upgrade to Apache Log4j 1-to-Log4j 2 bridge version 2.25.4, which corrects this issue. Note: The Apache Log4j 1-to-Log4j 2 bridge is deprecated and will not be present in Log4j 3. Users are encouraged to consult the Log4j 1 to Log4j 2 migration guide https://logging.apache.org/log4j/2.x/migrate-from-log4j1.html , and specifically the section on eliminating reliance on the bridge.
Severity
7.5 (High)
N/A (UNKNOWN)
References
{
"affected": [
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "liblog4j1.2-java",
"binary_version": "1.2.17-4ubuntu3+esm2"
}
]
},
"package": {
"ecosystem": "Ubuntu:Pro:14.04:LTS",
"name": "apache-log4j1.2",
"purl": "pkg:deb/ubuntu/apache-log4j1.2@1.2.17-4ubuntu3+esm2?arch=source\u0026distro=esm-infra-legacy/trusty"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"1.2.17-3ubuntu1",
"1.2.17-4ubuntu1",
"1.2.17-4ubuntu2",
"1.2.17-4ubuntu3",
"1.2.17-4ubuntu3+esm1",
"1.2.17-4ubuntu3+esm2"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "liblog4j2-java",
"binary_version": "2.4-2ubuntu0.1~esm1"
}
]
},
"package": {
"ecosystem": "Ubuntu:Pro:16.04:LTS",
"name": "apache-log4j2",
"purl": "pkg:deb/ubuntu/apache-log4j2@2.4-2ubuntu0.1~esm1?arch=source\u0026distro=esm-apps/xenial"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"2.2-1",
"2.4-1",
"2.4-2",
"2.4-2ubuntu0.1~esm1"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "liblog4j1.2-java",
"binary_version": "1.2.17-7ubuntu1+esm2"
}
]
},
"package": {
"ecosystem": "Ubuntu:Pro:16.04:LTS",
"name": "apache-log4j1.2",
"purl": "pkg:deb/ubuntu/apache-log4j1.2@1.2.17-7ubuntu1+esm2?arch=source\u0026distro=esm-apps/xenial"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"1.2.17-6ubuntu1",
"1.2.17-7ubuntu1",
"1.2.17-7ubuntu1+esm1",
"1.2.17-7ubuntu1+esm2"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "liblog4j1.2-java",
"binary_version": "1.2.17-8+deb10u1ubuntu0.2"
}
]
},
"package": {
"ecosystem": "Ubuntu:18.04:LTS",
"name": "apache-log4j1.2",
"purl": "pkg:deb/ubuntu/apache-log4j1.2@1.2.17-8+deb10u1ubuntu0.2?arch=source\u0026distro=bionic"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"1.2.17-7ubuntu2",
"1.2.17-8",
"1.2.17-8+deb10u1build0.18.04.1",
"1.2.17-8+deb10u1ubuntu0.1",
"1.2.17-8+deb10u1ubuntu0.2"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "liblog4j2-java",
"binary_version": "2.12.4-0ubuntu0.1"
}
]
},
"package": {
"ecosystem": "Ubuntu:18.04:LTS",
"name": "apache-log4j2",
"purl": "pkg:deb/ubuntu/apache-log4j2@2.12.4-0ubuntu0.1?arch=source\u0026distro=bionic"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"2.8.2-1",
"2.8.2-2",
"2.10.0-1",
"2.10.0-2",
"2.10.0-2ubuntu0.1",
"2.12.4-0ubuntu0.1"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "liblog4j1.2-java",
"binary_version": "1.2.17-9ubuntu0.2"
}
]
},
"package": {
"ecosystem": "Ubuntu:20.04:LTS",
"name": "apache-log4j1.2",
"purl": "pkg:deb/ubuntu/apache-log4j1.2@1.2.17-9ubuntu0.2?arch=source\u0026distro=focal"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"1.2.17-8",
"1.2.17-9",
"1.2.17-9ubuntu0.1",
"1.2.17-9ubuntu0.2"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "liblog4j2-java",
"binary_version": "2.17.1-0.20.04.1"
}
]
},
"package": {
"ecosystem": "Ubuntu:20.04:LTS",
"name": "apache-log4j2",
"purl": "pkg:deb/ubuntu/apache-log4j2@2.17.1-0.20.04.1?arch=source\u0026distro=focal"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"2.11.1-2",
"2.11.2-1",
"2.15.0-0.20.04.1",
"2.16.0-0.20.04.1",
"2.17.0-0.20.04.1",
"2.17.1-0.20.04.1"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "liblog4j1.2-java",
"binary_version": "1.2.17-11"
}
]
},
"package": {
"ecosystem": "Ubuntu:22.04:LTS",
"name": "apache-log4j1.2",
"purl": "pkg:deb/ubuntu/apache-log4j1.2@1.2.17-11?arch=source\u0026distro=jammy"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"1.2.17-10",
"1.2.17-11"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "liblog4j2-java",
"binary_version": "2.17.1-1"
}
]
},
"package": {
"ecosystem": "Ubuntu:22.04:LTS",
"name": "apache-log4j2",
"purl": "pkg:deb/ubuntu/apache-log4j2@2.17.1-1?arch=source\u0026distro=jammy"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"2.13.3-1",
"2.15.0-1",
"2.16.0-1",
"2.17.0-1",
"2.17.1-1"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "liblog4j1.2-java",
"binary_version": "1.2.17-11"
}
]
},
"package": {
"ecosystem": "Ubuntu:24.04:LTS",
"name": "apache-log4j1.2",
"purl": "pkg:deb/ubuntu/apache-log4j1.2@1.2.17-11?arch=source\u0026distro=noble"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"1.2.17-11"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "liblog4j2-java",
"binary_version": "2.19.0-2"
}
]
},
"package": {
"ecosystem": "Ubuntu:24.04:LTS",
"name": "apache-log4j2",
"purl": "pkg:deb/ubuntu/apache-log4j2@2.19.0-2?arch=source\u0026distro=noble"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"2.19.0-2"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "liblog4j1.2-java",
"binary_version": "1.2.17-11"
}
]
},
"package": {
"ecosystem": "Ubuntu:25.10",
"name": "apache-log4j1.2",
"purl": "pkg:deb/ubuntu/apache-log4j1.2@1.2.17-11?arch=source\u0026distro=questing"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"1.2.17-11"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "liblog4j2-java",
"binary_version": "2.19.0-2"
}
]
},
"package": {
"ecosystem": "Ubuntu:25.10",
"name": "apache-log4j2",
"purl": "pkg:deb/ubuntu/apache-log4j2@2.19.0-2?arch=source\u0026distro=questing"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"2.19.0-2"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "liblog4j1.2-java",
"binary_version": "1.2.17-11build1"
}
]
},
"package": {
"ecosystem": "Ubuntu:26.04:LTS",
"name": "apache-log4j1.2",
"purl": "pkg:deb/ubuntu/apache-log4j1.2@1.2.17-11build1?arch=source\u0026distro=resolute"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"1.2.17-11",
"1.2.17-11build1"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "liblog4j2-java",
"binary_version": "2.19.0-2build1"
}
]
},
"package": {
"ecosystem": "Ubuntu:26.04:LTS",
"name": "apache-log4j2",
"purl": "pkg:deb/ubuntu/apache-log4j2@2.19.0-2build1?arch=source\u0026distro=resolute"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"2.19.0-2",
"2.19.0-2build1"
]
}
],
"aliases": [],
"details": "The Log4j1XmlLayout from the Apache Log4j 1-to-Log4j 2 bridge fails to escape characters forbidden by the XML 1.0 standard, producing malformed XML output. Conforming XML parsers are required to reject documents containing such characters with a fatal error, which may cause downstream log processing systems to drop or fail to index affected records. Two groups of users are affected: * Those using Log4j1XmlLayout directly in a Log4j Core 2 configuration file. * Those using the Log4j 1 configuration compatibility layer with org.apache.log4j.xml.XMLLayout specified as the layout class. Users are advised to upgrade to Apache Log4j 1-to-Log4j 2 bridge version 2.25.4, which corrects this issue. Note: The Apache Log4j 1-to-Log4j 2 bridge is deprecated and will not be present in Log4j 3. Users are encouraged to consult the Log4j 1 to Log4j 2 migration guide https://logging.apache.org/log4j/2.x/migrate-from-log4j1.html , and specifically the section on eliminating reliance on the bridge.",
"id": "UBUNTU-CVE-2026-34479",
"modified": "2026-05-20T15:27:23Z",
"published": "2026-04-10T16:16:00Z",
"references": [
{
"type": "REPORT",
"url": "https://ubuntu.com/security/CVE-2026-34479"
},
{
"type": "REPORT",
"url": "https://www.cve.org/CVERecord?id=CVE-2026-34479"
},
{
"type": "REPORT",
"url": "https://lists.apache.org/thread/gd0hp6mj17rn3kj279vgy4p7kd4zz5on"
},
{
"type": "REPORT",
"url": "https://logging.apache.org/security.html#CVE-2026-34479"
},
{
"type": "REPORT",
"url": "https://github.com/apache/logging-log4j2/pull/4078"
},
{
"type": "REPORT",
"url": "https://logging.apache.org/cyclonedx/vdr.xml"
},
{
"type": "REPORT",
"url": "https://logging.apache.org/log4j/2.x/migrate-from-log4j1.html"
},
{
"type": "REPORT",
"url": "http://www.openwall.com/lists/oss-security/2026/04/10/8"
}
],
"related": [],
"schema_version": "1.7.0",
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N",
"type": "CVSS_V4"
},
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
"type": "CVSS_V3"
},
{
"score": "medium",
"type": "Ubuntu"
}
],
"upstream": [
"CVE-2026-34479"
]
}
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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.
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