CVE-2026-48693_CVE-2026-48693

5.5 / 10

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

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).

Basic Information

ID CVE-2026-48693

Source mitre

Published May 26, 2026 at 00:00

Modified May 26, 2026 at 20:33

Affected Product

Vendor n/a

Product n/a

Version n/a

Affected Versions n/a n/a n/a

CWE Classification

CWE-59

References

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    "published": "2026-05-26T00:00:00.000Z",
    "modified": "2026-05-26T20:33:37.827Z",
    "type": "cve",
    "title": "CVE-2026-48693",
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    "references": "https://github.com/pavel-odintsov/fastnetmon\nhttps://github.com/pavel-odintsov/fastnetmon/blob/master/src/fastnetmon.cpp\nhttps://github.com/pavel-odintsov/fastnetmon/blob/master/src/fastnetmon_logic.cpp\nhttps://lorikeetsecurity.com/blog/fastnetmon-cve-2026-48693-symlink-tmp",
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