In Ascertia SigningHub through 8.6.8, there is a lack of rate limiting on the invite user function, leading to an email bombing vulnerability. An authenticated attacker can exploit this by automating invite requests.
Conclusion & alert: CVE-2025-54320 is rated Low Risk (23/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.05%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
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 | 2025-12-20 | 0.02% | 0.05% | +0.03% |
| 2 | 2025-11-19 | — | 0.02% | — |
Full EPSS history (2 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 4.3 | 3.1 | MEDIUM |
|
2.8 | 1.4 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| ascertia | signinghub | <= 8.6.8 | cpe:2.3:a:ascertia:signinghub:*:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| https://github.com/saykino/CVE-2025-54320 | Third Party Advisory |
| https://www.ascertia.com/company/vulnerability-disclosure-policy/ | Vendor Advisory |