RCE in Folkertvanheusden Multitail
CVE-2026-55601
MultiTail is a utility for monitoring multiple log files in one terminal. In version 7.1.5 and earlier, the -ex and -eX execute-on-match feature appended attacker-controlled matched input to a configured command inside double quotes, then check_filter_exec() in mt.c passed the constructed command through execute_program() in exec.c to sh -c. Partial escaping left shell metacharacters such as command substitution active, allowing an attacker who could influence monitored input to execute commands as the user running MultiTail. No fixed release is available as of this review.
Vulnerability class: Command Injection (OS Command Injection)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.3 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
- Folkertvanheusden Multitail — versions <= 7.1.5
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-55601?
- CVE-2026-55601 is a high-severity vulnerability in Folkertvanheusden Multitail, classified under OS Command Injection. CVSS score: 7.3/10. Published 2026-10-13.
- How severe is CVE-2026-55601?
- High severity. CVSS v3 base score is 7.3 out of 10.