PatchTheCVECVE-2026-3999: A broken access control may allow an authenticated user to perform a horizontal privilege escalation
CVE-2026-3999 is a high-severity flaw (CVSS 8.8) affecting id server. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
A broken access control may allow an authenticated user to perform a horizontal privilege escalation. The vulnerability only impacts specific configurations.
Why this priority
- High severity
A fixed release or distro patch exists.
Risk facts
| CVSS score | 8.8 (High) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | Low |
| User interaction | None |
| EPSS exploit chance | 0.3% (top 74%) |
| CISA exploited list | No |
| Weakness | CWE-639 |
| Published | 2026-03-13 |
| Last modified | 2026-06-17 |
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-3999?
id server: upgrade to 9.0.0. Exact commands for each OS are on this page.
Is CVE-2026-3999 being exploited?
CVE-2026-3999 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-3999 affect?
CVE-2026-3999 affects id server. Severity is high (CVSS 8.8). A broken access control may allow an authenticated user to perform a horizontal privilege escalation. The vulnerability only impacts specific configurations.
How urgent is CVE-2026-3999?
Priority 37/100. High severity