CVE-2017-9781

Severity: medium (CVSS 6.1 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.4% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2017-06-21 · updated 2026-06-17
Weakness: CWE-79

Description

A cross site scripting (XSS) vulnerability exists in Check_MK versions 1.4.0x prior to 1.4.0p6, allowing an unauthenticated remote attacker to inject arbitrary HTML or JavaScript via the _username parameter when attempting authentication to webapi.py, which is returned unencoded with content type text/html.

Affected products

Tenable Check_MK: 1.4.0, 1.4.0-p1, 1.4.0-p2, 1.4.0-p3, 1.4.0-p4, 1.4.0-p5

References

http://git.mathias-kettner.de/git/?p=check_mk.git%3Ba=blob%3Bf=.werks/4757%3Bhb=c248f0b6ff7b15ced9f07a3df8a80fad656ea5b1
https://www.tenable.com/security/research/tra-2017-21
http://git.mathias-kettner.de/git/?p=check_mk.git%3Ba=blob%3Bf=.werks/4757%3Bhb=c248f0b6ff7b15ced9f07a3df8a80fad656ea5b1
https://www.tenable.com/security/research/tra-2017-21

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