SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2021-21748

ZTE MF971R product has two stack-based buffer overflow vulnerabilities.

CRITICAL 9.8EPSS 1.78%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.78%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

ZTE MF971R product has two stack-based buffer overflow vulnerabilities. An attacker could exploit the vulnerabilities to execute arbitrary code.

CVSS 3.1
9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
1.78% probability · 78th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-787
Affected
zte/mf971r firmware
Source
psirt@zte.com.cn
EPSS trend
0%3%5%26 October 2026: 1.78%26 October 202626 October 2026

EPSS 1.8% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.