UBUNTU-CVE-2026-48693

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Source
https://ubuntu.com/security/CVE-2026-48693
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-48693.json
JSON Data
https://api.osv.dev/v1/vulns/UBUNTU-CVE-2026-48693
Upstream
  • CVE-2026-48693
Published
2026-05-26T17:16:00Z
Modified
2026-06-15T20:15:15.366923946Z
Severity
  • 5.5 (Medium) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N CVSS Calculator
  • 5.5 (Medium) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N CVSS Calculator
  • Ubuntu - medium
Summary
[none]
Details

FastNetMon Community Edition through 1.2.9 is vulnerable to a local symlink attack via predictable file paths in /tmp. The statistics file path defaults to '/tmp/fastnetmon.dat' (src/fastnetmon.cpp line 159). The printscreencontentsintofile() function (src/fastnetmonlogic.cpp line 2186) opens this path with std::ios::trunc without checking for symlinks or using ONOFOLLOW. Additionally, the chmod() call on line 2190 always operates on clistatsfilepath regardless of which filepath parameter was passed (a bug that applies wrong permissions), and the umask is set to 0 during daemonization (src/fastnetmon.cpp line 1821), making all created files world-writable. A local attacker can exploit this to overwrite arbitrary files as the FastNetMon process user (typically root).

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_version": "1.1.3+dfsg-6build1",
            "binary_name": "fastnetmon"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-48693.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_version": "1.1.4-1ubuntu0.1~esm1",
            "binary_name": "fastnetmon"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-48693.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_version": "1.2.6-1ubuntu0.1~esm1",
            "binary_name": "fastnetmon"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-48693.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_version": "1.2.8+git20250911-1",
            "binary_name": "fastnetmon"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-48693.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_version": "1.2.8+git20250911-2ubuntu0.1~esm1",
            "binary_name": "fastnetmon"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-48693.json"