CVE-2021-20847

Cross-site scripting vulnerability in Wi-Fi STATION SH-52A (38JP_1_11G, 38JP_1_11J, 38JP_1_11K, 38JP_1_11L, 38JP_1_26F, 38JP_1_26G, 38JP_1_26J, 38JP_2_03B, and 38JP_2_03C) allows a remote unauthenticated attacker to inject an arbitrary script via WebUI of the device.

Published: 2021-12-01 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-20847 is rated Moderate Risk (45.4/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.45%). Mandatory action: Review affected assets and schedule 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-2021-20847

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 2025-03-30 0.71% 0.45% -0.26%
2 2025-03-29 0.45% 0.71% +0.26%
3 2025-03-17 0.45%

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-20847

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.1 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/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:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
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 2.7 [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-2021-20847

Affected software / configurations for CVE-2021-20847

Vendor Product Version Raw CPE
nttdocomo wi-fi_station_sh-52a_firmware 38jp_1_11g cpe:2.3:o:nttdocomo:wi-fi_station_sh-52a_firmware:38jp_1_11g:*:*:*:*:*:*:*
nttdocomo wi-fi_station_sh-52a_firmware 38jp_1_11j cpe:2.3:o:nttdocomo:wi-fi_station_sh-52a_firmware:38jp_1_11j:*:*:*:*:*:*:*
nttdocomo wi-fi_station_sh-52a_firmware 38jp_1_11k cpe:2.3:o:nttdocomo:wi-fi_station_sh-52a_firmware:38jp_1_11k:*:*:*:*:*:*:*
nttdocomo wi-fi_station_sh-52a_firmware 38jp_1_11l cpe:2.3:o:nttdocomo:wi-fi_station_sh-52a_firmware:38jp_1_11l:*:*:*:*:*:*:*
nttdocomo wi-fi_station_sh-52a_firmware 38jp_1_26f cpe:2.3:o:nttdocomo:wi-fi_station_sh-52a_firmware:38jp_1_26f:*:*:*:*:*:*:*
nttdocomo wi-fi_station_sh-52a_firmware 38jp_1_26g cpe:2.3:o:nttdocomo:wi-fi_station_sh-52a_firmware:38jp_1_26g:*:*:*:*:*:*:*
nttdocomo wi-fi_station_sh-52a_firmware 38jp_1_26j cpe:2.3:o:nttdocomo:wi-fi_station_sh-52a_firmware:38jp_1_26j:*:*:*:*:*:*:*
nttdocomo wi-fi_station_sh-52a_firmware 38jp_2_03b cpe:2.3:o:nttdocomo:wi-fi_station_sh-52a_firmware:38jp_2_03b:*:*:*:*:*:*:*
nttdocomo wi-fi_station_sh-52a_firmware 38jp_2_03c cpe:2.3:o:nttdocomo:wi-fi_station_sh-52a_firmware:38jp_2_03c:*:*:*:*:*:*:*

References for CVE-2021-20847

cvelogic Threat Intelligence