UBUNTU-CVE-2026-48685

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Source
https://ubuntu.com/security/CVE-2026-48685
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-48685.json
JSON Data
https://api.osv.dev/v1/vulns/UBUNTU-CVE-2026-48685
Upstream
Published
2026-05-26T16:16:00Z
Modified
2026-06-15T20:15:13.666755764Z
Severity
  • 6.5 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
  • 6.5 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
  • Ubuntu - medium
Summary
[none]
Details

FastNetMon Community Edition through 1.2.9 has out-of-bounds memory access because it incorrectly parses BGP path attributes with the extended length flag set. In src/bgpprotocol.hpp, the parserawbgpattribute() function correctly identifies when extendedlengthbit is set and sets lengthoflengthfield to 2, but then reads only a single byte for the attribute value length (attributevalue_length = value[2] at line 173). Per RFC 4271 Section 4.3, when the Extended Length bit is set, the Attribute Length field is two octets and the value should be read as a 16-bit big-endian integer from value[2] and value[3]. As a result, any attribute longer than 255 bytes has its length silently truncated to the low byte (e.g., 300 bytes = 0x012C is read as 0x2C = 44 bytes). The remaining 256 bytes are then misinterpreted as subsequent attributes, causing cascading parse failures and potential out-of-bounds memory access.

References

Affected packages

Ubuntu:18.04:LTS / fastnetmon

Package

Name
fastnetmon
Purl
pkg:deb/ubuntu/fastnetmon?arch=source&distro=bionic

Affected ranges

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

Affected versions

1.*
1.1.3+dfsg-3
1.1.3+dfsg-4
1.1.3+dfsg-6build1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "fastnetmon",
            "binary_version": "1.1.3+dfsg-6build1"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-48685.json"

Ubuntu:Pro:20.04:LTS / fastnetmon

Package

Name
fastnetmon
Purl
pkg:deb/ubuntu/fastnetmon?arch=source&distro=esm-apps%2Ffocal

Affected ranges

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

Affected versions

1.*
1.1.4-1
1.1.4-1build3
1.1.4-1build4
1.1.4-1build5
1.1.4-1ubuntu0.1~esm1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "fastnetmon",
            "binary_version": "1.1.4-1ubuntu0.1~esm1"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-48685.json"

Ubuntu:Pro:24.04:LTS / fastnetmon

Package

Name
fastnetmon
Purl
pkg:deb/ubuntu/fastnetmon?arch=source&distro=esm-apps%2Fnoble

Affected ranges

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

Affected versions

1.*
1.2.5-1
1.2.6-1
1.2.6-1build1
1.2.6-1build2
1.2.6-1build3
1.2.6-1build4
1.2.6-1ubuntu0.1~esm1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "fastnetmon",
            "binary_version": "1.2.6-1ubuntu0.1~esm1"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-48685.json"

Ubuntu:25.10 / fastnetmon

Package

Name
fastnetmon
Purl
pkg:deb/ubuntu/fastnetmon?arch=source&distro=questing

Affected ranges

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

Affected versions

1.*
1.2.8-1build1
1.2.8-1build2
1.2.8+git20250911-1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "fastnetmon",
            "binary_version": "1.2.8+git20250911-1"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-48685.json"

Ubuntu:Pro:26.04:LTS / fastnetmon

Package

Name
fastnetmon
Purl
pkg:deb/ubuntu/fastnetmon?arch=source&distro=esm-apps%2Fresolute

Affected ranges

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

Affected versions

1.*
1.2.8+git20250911-1
1.2.8+git20250911-1build1
1.2.8+git20250911-1build2
1.2.8+git20250911-2
1.2.8+git20250911-2ubuntu0.1~esm1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "fastnetmon",
            "binary_version": "1.2.8+git20250911-2ubuntu0.1~esm1"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-48685.json"