PatchTheCVECVE-2026-48693: FastNetMon Community Edition through 1.2.9 is vulnerable to a local symlink attack via predictable file paths
CVE-2026-48693 is a medium-severity flaw (CVSS 5.5) affecting fastnetmon. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
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_st
Why this priority
- No elevated risk signals yet
A fixed release or distro patch exists.
Risk facts
| CVSS score | 5.5 (Medium) |
| Attack vector | Local |
| Attack complexity | Low |
| Privileges needed | Low |
| User interaction | None |
| EPSS exploit chance | 0.1% (top 98%) |
| CISA exploited list | No |
| Weakness | CWE-59 |
| Published | 2026-05-26 |
| Last modified | 2026-07-24 |
Last updated 2026-07-24 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-48693?
fastnetmon: upgrade to newer than 1.2.9. Exact commands for each OS are on this page.
Is CVE-2026-48693 being exploited?
CVE-2026-48693 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-48693 affect?
CVE-2026-48693 affects fastnetmon. Severity is medium (CVSS 5.5). 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_
How urgent is CVE-2026-48693?
Priority 20/100. No elevated risk signals yet.
Software pages
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