A Host Header Poisoning vulnerability exists in Monica 4.1.2 due to improper handling of the HTTP Host header in app/Providers/AppServiceProvider.php, combined with the default misconfiguration where the "app.force_url" is not set and default is "false". The application generates absolute URLs (such as those used in password reset emails) using the user-supplied Host header. This allows remote attackers to poison the password reset link sent to a victim,
Conclusion & alert: CVE-2026-26747 is rated Exploit Available (57.1/100): CVSS Critical severity, with low exploitation likelihood (EPSS 0.05%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
| EDB-ID | Source | Kind | Published | Link |
|---|---|---|---|---|
| — | nvd_ref | exploit_tag | Exploit-DB ↗ |
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-02-26 | 0.04% | 0.05% | +0.01% |
| 2 | 2026-02-24 | 0.05% | 0.04% | -0.01% |
| 3 | 2026-02-21 | — | 0.05% | — |
Full EPSS history (3 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 9.1 | 3.1 | CRITICAL |
|
3.9 | 5.2 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
| URL | Tags |
|---|---|
| https://github.com/hungnqdz/cve-research/blob/main/CVE-2026-26747.md | Exploit Vendor Advisory |
| https://github.com/monicahq/monica | Product |