CVE-2026-48693
Summary
| CVE | CVE-2026-48693 |
|---|---|
| State | PUBLISHED |
| Assigner | mitre |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-05-26 17:16:53 UTC |
| Updated | 2026-05-27 14:42:18 UTC |
| Description | 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 print_screen_contents_into_file() function (src/fastnetmon_logic.cpp line 2186) opens this path with std::ios::trunc without checking for symlinks or using O_NOFOLLOW. Additionally, the chmod() call on line 2190 always operates on cli_stats_file_path regardless of which file_path 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). |
Risk And Classification
Primary CVSS: v3.1 5.5 MEDIUM from [email protected]
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
Problem Types: CWE-59 | n/a | CWE-59 CWE-59 Improper Link Resolution Before File Access ('Link Following')
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Primary | 5.5 | MEDIUM | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N |
| 3.1 | ADP | DECLARED | 5.5 | MEDIUM | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N |
| 3.1 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | Secondary | 5.5 | MEDIUM | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N |
CVSS v3.1 Breakdown
Attack Vector
LocalAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
HighAvailability
NoneCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Application | Pavel-odintsov | Fastnetmon | All | All | All | All |
Vendor Declared Affected Products
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/pavel-odintsov/fastnetmon | [email protected] | github.com | Product |
| lorikeetsecurity.com/blog/fastnetmon-cve-2026-48693-symlink-tmp | [email protected] | lorikeetsecurity.com | Third Party Advisory |
| github.com/pavel-odintsov/fastnetmon/blob/master/src/fastnetmon_logic.cpp | [email protected] | github.com | Product |
| github.com/pavel-odintsov/fastnetmon/blob/master/src/fastnetmon.cpp | [email protected] | github.com | Product |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.