CVE-2021-21745

ZTE MF971R product has a Referer authentication bypass vulnerability. Without CSRF verification, an attackercould use this vulnerability to perform illegal authorization operations by sending a request to the user to click.

Published: 2021-10-20 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-21745 is rated Moderate Risk (47/100): CVSS Medium severity, with high exploitation likelihood (EPSS 36.41%, 97th percentile). EPSS ranks this CVE among the most likely to be exploited in the near term. High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-21745

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 2026-04-20 40.59% 36.41% -4.18%
2 2025-11-21 25.07% 40.59% +15.51%
3 2025-11-18 — 25.07% —

Full EPSS history (43 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-21745

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 1.4 [email protected]
4.3 2.0 MEDIUM
AV:N/AC:M/Au:N/C:N/I:P/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 8.6 2.9 [email protected]

Weakness enumeration for CVE-2021-21745

Affected software / configurations for CVE-2021-21745

Vendor Product Version Raw CPE
zte mf971r_firmware v1.0.0b05 cpe:2.3:o:zte:mf971r_firmware:v1.0.0b05:*:*:*:*:*:*:*
zte mf971r_firmware 1v1.0.0b06 cpe:2.3:o:zte:mf971r_firmware:1v1.0.0b06:*:*:*:*:*:*:*
zte mf971r_firmware 2v1.0.0b03 cpe:2.3:o:zte:mf971r_firmware:2v1.0.0b03:*:*:*:*:*:*:*
zte mf971r_firmware s2v1.0.0b03 cpe:2.3:o:zte:mf971r_firmware:s2v1.0.0b03:*:*:*:*:*:*:*
zte mf971r_firmware sv1.0.0b05 cpe:2.3:o:zte:mf971r_firmware:sv1.0.0b05:*:*:*:*:*:*:*

References for CVE-2021-21745

cvelogic Threat Intelligence