CVE-2019-11454

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.4% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2019-04-22 · updated 2026-06-17
Weakness: CWE-79

Description

Persistent cross-site scripting (XSS) in http/cervlet.c in Tildeslash Monit before 5.25.3 allows a remote unauthenticated attacker to introduce arbitrary JavaScript via manipulation of an unsanitized user field of the Authorization header for HTTP Basic Authentication, which is mishandled during an _viewlog operation.

Affected products

Canonical Ubuntu Linux: 18.10, 19.04
Debian Linux: 8.0, 9.0
Fedoraproject Fedora: 31, 32
Tildeslash Ltd. monit: before 5.25.3 — fixed in 5.25.3

How to fix

Upgrade to a fixed version: Tildeslash Ltd. monit 5.25.3. Check the vendor advisory for mitigations.

References

https://bitbucket.org/tildeslash/monit/commits/1a8295eab6815072a18019b668fe084945b751f3
https://bitbucket.org/tildeslash/monit/commits/328f60773057641c4b2075fab9820145e95b728c
https://github.com/dzflack/exploits/blob/master/unix/monit_xss.py
https://lists.debian.org/debian-lts-announce/2019/04/msg00028.html
https://lists.debian.org/debian-lts-announce/2021/12/msg00018.html
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HZQDHRSKTEX5MSYXNCGFTUSFGANBARHX/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L475QJMFFI2QV5QEHAKKPVX6QX6ECUL6/
https://usn.ubuntu.com/3971-1/
https://bitbucket.org/tildeslash/monit/commits/1a8295eab6815072a18019b668fe084945b751f3
https://bitbucket.org/tildeslash/monit/commits/328f60773057641c4b2075fab9820145e95b728c
https://github.com/dzflack/exploits/blob/master/unix/monit_xss.py
https://lists.debian.org/debian-lts-announce/2019/04/msg00028.html

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