In Terramaster F4-210, F2-210 TOS 4.2.X (4.2.15-2107141517), an attacker can self-sign session cookies by knowing the target's MAC address and the user's password hash. Guest users (disabled by default) can be abused using a null/empty hash and allow an unauthenticated attacker to login as guest.
Conclusion & alert: CVE-2021-45841 is rated High Exploit Risk (86.8/100): CVSS High severity, with high exploitation likelihood (EPSS 65.51%, 98th percentile). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). EPSS rose +17.98% over the last day, indicating growing attacker interest. 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 | 2025-11-21 | 47.53% | 65.51% | +17.98% |
| 2 | 2025-11-18 | 65.51% | 47.53% | -17.98% |
| 3 | 2025-10-02 | — | 65.51% | — |
Full EPSS history (16 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 8.1 | 3.1 | HIGH |
|
2.2 | 5.9 | [email protected] |
| 6.8 | 2.0 | MEDIUM |
|
8.6 | 6.4 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| terra-master | tos | 4.2.15-2107141517 | cpe:2.3:o:terra-master:tos:4.2.15-2107141517:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| http://packetstormsecurity.com/files/172881/TerraMaster-TOS-4.2.15-Remote-Code-Execution.html | |
| https://thatsn0tmy.site/posts/2021/12/how-to-summon-rces/ | Exploit Third Party Advisory |