Cyber Resilience

CVE-2021-34991

High

Published: 15 November 2021

Published
15 November 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 8.8 CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0030 53.3th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-34991 is a high-severity Stack-based Buffer Overflow (CWE-121) vulnerability in Netgear Ex3700 Firmware. Its CVSS base score is 8.8 (High).

Operationally, ranked in the top 46.7% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of NETGEAR R6400v2 1.0.4.106_10.0.80 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the UPnP service, which listens on TCP port 5000 by…

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default. When parsing the uuid request header, the process does not properly validate the length of user-supplied data prior to copying it to a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-14110.

CWE(s)

Related Threats

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

Affected Assets

netgear
ex3700 firmware
≤ 1.0.0.94
netgear
ex3800 firmware
≤ 1.0.0.94
netgear
ex6120 firmware
≤ 1.0.0.66
netgear
ex6130 firmware
≤ 1.0.0.66
netgear
r6400 firmware
≤ 1.0.1.76
netgear
r6400v2 firmware
≤ 1.0.4.120
netgear
r6700v3 firmware
≤ 1.0.4.120
netgear
r6900p firmware
≤ 1.3.3.142
netgear
r7000 firmware
≤ 1.0.11.128
netgear
r7000p firmware
≤ 1.3.3.142
+34 more product configuration(s) — see NVD for full list

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-787

Out-of-bounds writes that corrupt control flow or inject shellcode are rendered non-executable by the same memory protections.

References