UBUNTU-CVE-2026-15576

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Source

https://ubuntu.com/security/CVE-2026-15576

Import Source

https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-15576.json

JSON Data

https://api.osv.dev/v1/vulns/UBUNTU-CVE-2026-15576

Upstream

CVE-2026-15576

Published

2026-08-21T11:17:00Z

Modified

2026-09-02T19:34:38Z

Severity

6.9 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N CVSS Calculator
Ubuntu - medium

Summary

[none]

Details

Improper authentication in the agent receiver of Checkmk <2.5.0p10 allows an unauthenticated remote attacker to bypass mutual TLS client certificate verification of relay endpoints by supplying a fixed placeholder identity in the request URL, resulting in limited impact on integrity and availability. Only the Cloud, Ultimate and Ultimate MT editions are affected, as other editions do not expose relay endpoints.

References

Affected packages

Ubuntu:Pro:16.04:LTS / check-mk

Package

Name: check-mk
Purl: pkg:deb/ubuntu/check-mk?arch=source&distro=esm-apps%2Fxenial

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0 Unknown introduced version / All previous versions are affected

Affected versions

1.*

1.2.6p5-1

1.2.6p12-1

1.2.6p12-1ubuntu0.16.04.1

1.2.6p12-1ubuntu0.16.04.1+esm1

Ecosystem specific

{
    "binaries":  [
        {
            "binary_name":  "check-mk-agent",
            "binary_version":  "1.2.6p12-1ubuntu0.16.04.1+esm1"
        },
        {
            "binary_name":  "check-mk-agent-logwatch",
            "binary_version":  "1.2.6p12-1ubuntu0.16.04.1+esm1"
        },
        {
            "binary_name":  "check-mk-config-icinga",
            "binary_version":  "1.2.6p12-1ubuntu0.16.04.1+esm1"
        },
        {
            "binary_name":  "check-mk-config-nagios3",
            "binary_version":  "1.2.6p12-1ubuntu0.16.04.1+esm1"
        },
        {
            "binary_name":  "check-mk-livestatus",
            "binary_version":  "1.2.6p12-1ubuntu0.16.04.1+esm1"
        },
        {
            "binary_name":  "check-mk-multisite",
            "binary_version":  "1.2.6p12-1ubuntu0.16.04.1+esm1"
        },
        {
            "binary_name":  "check-mk-server",
            "binary_version":  "1.2.6p12-1ubuntu0.16.04.1+esm1"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-15576.json"

Ubuntu:18.04:LTS / check-mk