Cyber Resilience

CVE-2021-20844

Medium

Published: 24 November 2021

Published
24 November 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 5.7 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N
EPSS Score 0.0034 57.0th percentile
Risk Priority 12 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-20844 is a medium-severity Improper Encoding or Escaping of Output (CWE-116) vulnerability in Yamaha Rtx830 Firmware. Its CVSS base score is 5.7 (Medium).

Operationally, ranked in the top 43.0% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

Improper neutralization of HTTP request headers for scripting syntax vulnerability in the Web GUI of RTX830 Rev.15.02.17 and earlier, NVR510 Rev.15.01.18 and earlier, NVR700W Rev.15.00.19 and earlier, and RTX1210 Rev.14.01.38 and earlier allows a remote authenticated attacker to obtain sensitive…

more

information via a specially crafted web page.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

yamaha
rtx830 firmware
≤ 15.02.17
yamaha
nvr510 firmware
≤ 15.01.18
yamaha
nvr700w firmware
≤ 15.00.19
yamaha
rtx1210 firmware
≤ 14.01.38
ntt-west
biz box rtx830 firmware
≤ 15.02.17
ntt-west
biz box nvr510 firmware
≤ 15.01.18
ntt-west
biz box nvr700w firmware
≤ 15.00.19
ntt-west
biz box rtx1210 firmware
≤ 14.01.38

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-116

Validating that output matches expected content directly mitigates failures to properly encode or escape data for its destination context.

References