What is CVE-2026-27728?

CVE-2026-27728 is a critical-severity vulnerability in Hackerbay Oneuptime, classified under OS Command Injection. CVSS score: 9.9/10. Published 2026-02-25.

How severe is CVE-2026-27728?

Critical severity. CVSS v3 base score is 9.9 out of 10.

RCE in Hackerbay Oneuptime

CVE-2026-27728

OneUptime is a solution for monitoring and managing online services. Prior to version 10.0.7, an OS command injection vulnerability in `NetworkPathMonitor.performTraceroute()` allows any authenticated project user to execute arbitrary operating system commands on the Probe server by injecting shell metacharacters into a monitor's destination field. Version 10.0.7 fixes the vulnerability.

Vulnerability class: Command Injection (OS Command Injection)

Published 2026-02-25 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.9 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.025 (84.4th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 84th percentile — 84.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.017 · newest: 0.025 · change: +0.008

Affected products

Hackerbay Oneuptime
Oneuptime — versions < 10.0.7

Weakness classification (CWE)

CWE-78 — OS Command Injection

References

github.com/OneUptime/oneuptime/security/advisories/GHSA-jmhp-5558-qxh5 (Exploit, Vendor Advisory)
github.com/OneUptime/oneuptime/commit/f2cce35a04fac756cecc7a4c55e23758b99288c1 (Patch)

Frequently asked questions

What is CVE-2026-27728?: CVE-2026-27728 is a critical-severity vulnerability in Hackerbay Oneuptime, classified under OS Command Injection. CVSS score: 9.9/10. Published 2026-02-25.
How severe is CVE-2026-27728?: Critical severity. CVSS v3 base score is 9.9 out of 10.