CVE & CISA-KEV Catalog

CVE-2021-34947

HIGH
8.8
CVSS v3
NVD

Description

NETGEAR R7800 net-cgi Out-Of-Bounds Write Remote Code Execution Vulnerability. This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of NETGEAR R7800 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the parsing of the soap_block_table file. The issue results from the lack of proper validation of user-supplied data, which can result in a write past the end of an allocated data structure. An attacker can leverage this vulnerability to execute code in the context of root. . Was ZDI-CAN-13055.

CWE-787Out-of-bounds Write

How to fix

Remediation Available
d7800 firmwareNVD
Affected:< 1.0.1.64Fixed in:1.0.1.64CVE-2021-34947derived from NVD
ex2700 firmwareNVD
Affected:< 1.0.1.66Fixed in:1.0.1.66CVE-2021-34947derived from NVD
ex6100 firmwareNVD
Affected:< 1.0.1.106Fixed in:1.0.1.106CVE-2021-34947derived from NVD
ex6150 firmwareNVD
Affected:< 1.0.1.106Fixed in:1.0.1.106CVE-2021-34947derived from NVD
ex6200 firmwareNVD
Affected:< 1.0.1.86Fixed in:1.0.1.86CVE-2021-34947derived from NVD
ex6250 firmwareNVD
Affected:< 1.0.0.146Fixed in:1.0.0.146CVE-2021-34947derived from NVD
ex6400 firmwareNVD
Affected:< 1.0.2.164Fixed in:1.0.2.164CVE-2021-34947derived from NVD
ex6400v2 firmwareNVD
Affected:< 1.0.0.146Fixed in:1.0.0.146CVE-2021-34947derived from NVD
ex6410 firmwareNVD
Affected:< 1.0.0.146Fixed in:1.0.0.146CVE-2021-34947derived from NVD
ex6420 firmwareNVD
Affected:< 1.0.0.146Fixed in:1.0.0.146CVE-2021-34947derived from NVD
ex6500v1 firmwareNVD
Affected:< 1.0.0.146Fixed in:1.0.0.146CVE-2021-34947derived from NVD
ex7300 firmwareNVD
Affected:< 1.0.2.164Fixed in:1.0.2.164CVE-2021-34947derived from NVD
ex7300v2 firmwareNVD
Affected:< 1.0.0.146Fixed in:1.0.0.146CVE-2021-34947derived from NVD
ex7320 firmwareNVD
Affected:< 1.0.0.146Fixed in:1.0.0.146CVE-2021-34947derived from NVD
ex7700 firmwareNVD
Affected:< 1.0.0.222Fixed in:1.0.0.222CVE-2021-34947derived from NVD
ex8000 firmwareNVD
Affected:< 1.0.1.238Fixed in:1.0.1.238CVE-2021-34947derived from NVD
lbr1020 firmwareNVD
Affected:< 2.6.5.32Fixed in:2.6.5.32CVE-2021-34947derived from NVD
lbr20 firmwareNVD
Affected:< 2.6.5.32Fixed in:2.6.5.32CVE-2021-34947derived from NVD
r6700ax firmwareNVD
Affected:< 1.0.5.108Fixed in:1.0.5.108CVE-2021-34947derived from NVD
r7800 firmwareNVD
Affected:< 1.0.2.84Fixed in:1.0.2.84CVE-2021-34947derived from NVD
r8900 firmwareNVD
Affected:< 1.0.5.36Fixed in:1.0.5.36CVE-2021-34947derived from NVD
r9000 firmwareNVD
Affected:< 1.0.5.36Fixed in:1.0.5.36CVE-2021-34947derived from NVD
rax10 firmwareNVD
Affected:< 1.0.5.108Fixed in:1.0.5.108CVE-2021-34947derived from NVD
rax120 firmwareNVD
Affected:< 1.2.2.24Fixed in:1.2.2.24CVE-2021-34947derived from NVD
rax120v2 firmwareNVD
Affected:< 1.2.2.24Fixed in:1.2.2.24CVE-2021-34947derived from NVD
rax70 firmwareNVD
Affected:< 1.0.5.108Fixed in:1.0.5.108CVE-2021-34947derived from NVD
rax78 firmwareNVD
Affected:< 1.0.5.108Fixed in:1.0.5.108CVE-2021-34947derived from NVD
rbr10 firmwareNVD
Affected:< 2.7.4.24Fixed in:2.7.4.24CVE-2021-34947derived from NVD
rbr20 firmwareNVD
Affected:< 2.7.4.24Fixed in:2.7.4.24CVE-2021-34947derived from NVD
rbr40 firmwareNVD
Affected:< 2.7.4.24Fixed in:2.7.4.24CVE-2021-34947derived from NVD
rbr50 firmwareNVD
Affected:< 2.7.4.24Fixed in:2.7.4.24CVE-2021-34947derived from NVD
rbs10 firmwareNVD
Affected:< 2.7.4.24Fixed in:2.7.4.24CVE-2021-34947derived from NVD
rbs20 firmwareNVD
Affected:< 2.7.4.24Fixed in:2.7.4.24CVE-2021-34947derived from NVD
rbs40 firmwareNVD
Affected:< 2.7.4.24Fixed in:2.7.4.24CVE-2021-34947derived from NVD
rbs50 firmwareNVD
Affected:< 2.7.4.24Fixed in:2.7.4.24CVE-2021-34947derived from NVD
rbs50y firmwareNVD
Affected:< 2.7.4.12Fixed in:2.7.4.12CVE-2021-34947derived from NVD
wn3000rpv2 firmwareNVD
Affected:< 1.0.0.88Fixed in:1.0.0.88CVE-2021-34947derived from NVD
wnr2000v5 firmwareNVD
Affected:< 1.0.0.78Fixed in:1.0.0.78CVE-2021-34947derived from NVD
xr450 firmwareNVD
Affected:< 2.3.2.130Fixed in:2.3.2.130CVE-2021-34947derived from NVD
xr500 firmwareNVD
Affected:< 2.3.2.130Fixed in:2.3.2.130CVE-2021-34947derived from NVD
xr700 firmwareNVD
Affected:< 1.0.1.44Fixed in:1.0.1.44CVE-2021-34947derived from NVD

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorAdjacent
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged

Impact

ConfidentialityHigh
IntegrityHigh
AvailabilityHigh

CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exploit Intelligence

0.55%probability of exploitation in 30 days
42ndpercentile

Moderate risk: more likely to be exploited than 42% of all known CVEs.

References

Related Vulnerabilities

Other CWE-787 (Out-of-bounds Write) vulnerabilities, ordered by exploit likelihood. View all

CVESeverityCVSSEPSSExploitedFix
CVE-2025-22457Critical9.0100%KEV + RansomFix
CVE-2025-0282Critical9.0100%KEV + Ransom-
CVE-2015-3113Critical9.8100%KEVFix
CVE-2021-20038Critical9.8100%KEV + Ransom-
CVE-2023-4863High8.8100%KEVFix
CVE-2020-16040Medium6.5100%-Fix
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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2025-08-14.