PatchTheCEVCVE-2026-8078: Stored cross-site scripting in the global settings change log in Checkmk <2.5.0p5, <2.4.0p31, <2.3.0p48, and a
20
Routine
MEDIUM 4.8DOWNGRADE
CVE-2026-8078 is a medium-severity flaw (CVSS 4.8) affecting checkmk. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
Stored cross-site scripting in the global settings change log in Checkmk <2.5.0p5, <2.4.0p31, <2.3.0p48, and all 2.2.0 versions allows an administrator who can change global settings to store malicious HTML or JavaScript in changelog messages that executes in other users' browsers when they view the Activate Changes page or Audit log.
Why this priority
- No elevated risk signals yet
No fix is published yet: follow the downgrade or mitigation steps.
Risk facts
| CVSS score | 4.8 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | High |
| User interaction | Required |
| EPSS exploit chance | 0.2% (top 85%) |
| CISA exploited list | No |
| Weakness | CWE-79 |
| Published | 2026-06-08 |
| Last modified | 2026-10-23 |
Publisher (CNA): Checkmk GmbH · Vendor: checkmk
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
checkmk checkmk DOWNGRADE
Affected: 2.2.0 · 2.2.0 b1 · 2.2.0 b2 · 2.2.0 b3 · 2.2.0 b4 · 2.2.0 b5 · 2.2.0 b6 · 2.2.0 b7
Fixed in: no fixed release known
Safe to downgrade to: a release before 2.2.0
1. Check installed version
apt-cache policy checkmk || rpm -q checkmk || checkmk --version
2. No fixed release: DOWNGRADE to a release before 2.2.0 (Debian / Ubuntu)
apt-cache madison checkmk
sudo apt install checkmk=<VERSION_BEFORE_2.2.0>
sudo apt-mark hold checkmk
2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list checkmk
sudo dnf downgrade checkmk-<VERSION_BEFORE_2.2.0>
sudo dnf versionlock add checkmk
Downgrade risk
Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.
After downgrade
Restart the service, and keep the package held until a fixed release ships.
Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Related CVEs
- CVE-2026-33456 HIGH 7.6 DOWNGRADE Livestatus injection in the notification test mode in Checkmk <2.5.0b4 and <2.4.0p26 allows an authenticated u
- CVE-2024-47091 HIGH 7.8 DOWNGRADE Privilege escalation in the mk_mysql agent plugin on Windows in Checkmk <2.4.0p29, <2.3.0p47, and 2.2.0 (EOL)
- CVE-2023-22348 MEDIUM 4.3 DOWNGRADE UPGRADE Improper Authorization in RestAPI in Checkmk GmbH's Checkmk versions <2.1.0p28 and <2.2.0b8 allows remote auth
- CVE-2023-23548 MEDIUM 5.4 UPGRADE Reflected XSS in business intelligence in Checkmk <2.2.0p8, <2.1.0p32, <2.0.0p38, <=1.6.0p30.
- CVE-2026-33457 MEDIUM 6.3 DOWNGRADE Livestatus injection in the prediction graph page in Checkmk <2.5.0b4, <2.4.0p26, and <2.3.0p47 allows an auth