UBUNTU-CVE-2025-12543

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Source
https://ubuntu.com/security/CVE-2025-12543
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-12543.json
JSON Data
https://api.osv.dev/v1/vulns/UBUNTU-CVE-2025-12543
Upstream
  • CVE-2025-12543
Published
2026-01-08T00:00:00Z
Modified
2026-01-08T06:30:00.539034Z
Severity
  • 9.6 (Critical) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L CVSS Calculator
  • Ubuntu - high
Summary
[none]
Details

A flaw was found in the Undertow HTTP server core, which is used in WildFly, JBoss EAP, and other Java applications. The Undertow library fails to properly validate the Host header in incoming HTTP requests.As a result, requests containing malformed or malicious Host headers are processed without rejection, enabling attackers to poison caches, perform internal network scans, or hijack user sessions.

References

Affected packages

Ubuntu:16.04:LTS

undertow

Package

Name
undertow
Purl
pkg:deb/ubuntu/undertow@1.3.16-1?arch=source&distro=xenial

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

1.*

1.3.4-1
1.3.5-1
1.3.7-1
1.3.11-1
1.3.16-1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "libundertow-java",
            "binary_version": "1.3.16-1"
        }
    ],
    "priority_reason": "user sesison takeover"
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-12543.json"

Ubuntu:18.04:LTS

undertow

Package

Name
undertow
Purl
pkg:deb/ubuntu/undertow@1.4.23-3?arch=source&distro=bionic

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

1.*

1.4.20-1
1.4.21-1
1.4.22-1
1.4.23-1
1.4.23-2build1
1.4.23-3

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "libundertow-java",
            "binary_version": "1.4.23-3"
        }
    ],
    "priority_reason": "user sesison takeover"
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-12543.json"

Ubuntu:20.04:LTS

undertow

Package

Name
undertow
Purl
pkg:deb/ubuntu/undertow@2.0.29-1?arch=source&distro=focal

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

2.*

2.0.23-1
2.0.27-1
2.0.28-1
2.0.29-1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "libundertow-java",
            "binary_version": "2.0.29-1"
        }
    ],
    "priority_reason": "user sesison takeover"
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-12543.json"

Ubuntu:22.04:LTS

undertow

Package

Name
undertow
Purl
pkg:deb/ubuntu/undertow@2.2.16-1?arch=source&distro=jammy

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

2.*

2.2.8-1
2.2.12-1
2.2.13-1
2.2.14-1
2.2.16-1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "libundertow-java",
            "binary_version": "2.2.16-1"
        }
    ],
    "priority_reason": "user sesison takeover"
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-12543.json"

Ubuntu:24.04:LTS

undertow

Package

Name
undertow
Purl
pkg:deb/ubuntu/undertow@2.3.8-2?arch=source&distro=noble

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

2.*

2.3.8-2

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "libundertow-java",
            "binary_version": "2.3.8-2"
        }
    ],
    "priority_reason": "user sesison takeover"
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-12543.json"

Ubuntu:25.04

undertow

Package

Name
undertow
Purl
pkg:deb/ubuntu/undertow@2.3.18-1?arch=source&distro=plucky

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

2.*

2.3.8-2
2.3.18-1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "libundertow-java",
            "binary_version": "2.3.18-1"
        }
    ],
    "priority_reason": "user sesison takeover"
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-12543.json"

Ubuntu:25.10

undertow

Package

Name
undertow
Purl
pkg:deb/ubuntu/undertow@2.3.18-2?arch=source&distro=questing

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

2.*

2.3.18-1
2.3.18-2

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "libundertow-java",
            "binary_version": "2.3.18-2"
        }
    ],
    "priority_reason": "user sesison takeover"
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-12543.json"