CVE-2021-27253

highpriority · track · 35EPSS 0.011 · 66 %ileEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

1.13% (66th) EPSS

CVSS 8.3 · high

Is it mine?

44 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of NETGEAR Nighthawk R7800. Although authentication is required to exploit this vulnerability, the existing authentication mechanism can be bypassed. The specific flaw exists within the handling of the rc_service parameter provided to apply_bind.cgi. The issue results from the lack of proper validation of a user-supplied string before using it to execute a system call. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-12303.

cvss

Technical severity, 0–10. One row per scoring source.

8.8

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.08.3highAV:A/AC:L/Au:N/C:C/I:C/A:Cprimary · NVD / NIST USexploitability 6.5 · impact 10

v3.18.8highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 5.9

v3.08.8highCVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · ENISA EU

v3.08.8highCVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · zdi-disclosures@trendmicro.comexploitability 2.8 · impact 5.9

v3.18.1highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-787USprimaryCWE-122US

affected products (44)

Products and version ranges known to be affected.

NETGEAR R7800≤ firmware version 1.0.2.76enisa_euvdEU
netgear br200 firmware< 5.10.0.5nvdUScpe:2.3:o:netgear:br200_firmware:*:*:*:*:*:*:*:*
netgear br500 firmware< 5.10.0.5nvdUScpe:2.3:o:netgear:br500_firmware:*:*:*:*:*:*:*:*
netgear d7800 firmware< 1.0.1.60nvdUScpe:2.3:o:netgear:d7800_firmware:*:*:*:*:*:*:*:*
netgear ex6100v2 firmware< 1.0.1.98nvdUScpe:2.3:o:netgear:ex6100v2_firmware:*:*:*:*:*:*:*:*
netgear ex6150 firmware< 1.0.1.98nvdUScpe:2.3:o:netgear:ex6150_firmware:*:*:*:*:*:*:*:*
netgear ex6250 firmware< 1.0.0.134nvdUScpe:2.3:o:netgear:ex6250_firmware:*:*:*:*:*:*:*:*
netgear ex6400 firmware< 1.0.2.158nvdUScpe:2.3:o:netgear:ex6400_firmware:*:*:*:*:*:*:*:*
netgear ex6400v2 firmware< 1.0.0.134nvdUScpe:2.3:o:netgear:ex6400v2_firmware:*:*:*:*:*:*:*:*
netgear ex6410 firmware< 1.0.0.134nvdUScpe:2.3:o:netgear:ex6410_firmware:*:*:*:*:*:*:*:*
netgear ex6420 firmware< 1.0.0.134nvdUScpe:2.3:o:netgear:ex6420_firmware:*:*:*:*:*:*:*:*
netgear ex7300 firmware< 1.0.2.158nvdUScpe:2.3:o:netgear:ex7300_firmware:*:*:*:*:*:*:*:*
netgear ex7300v2 firmware< 1.0.0.134nvdUScpe:2.3:o:netgear:ex7300v2_firmware:*:*:*:*:*:*:*:*
netgear ex7320 firmware< 1.0.0.134nvdUScpe:2.3:o:netgear:ex7320_firmware:*:*:*:*:*:*:*:*
netgear ex7700 firmware< 1.0.0.216nvdUScpe:2.3:o:netgear:ex7700_firmware:*:*:*:*:*:*:*:*
netgear ex8000 firmware< 1.0.1.232nvdUScpe:2.3:o:netgear:ex8000_firmware:*:*:*:*:*:*:*:*
netgear lbr20 firmware< 2.6.3.50nvdUScpe:2.3:o:netgear:lbr20_firmware:*:*:*:*:*:*:*:*
netgear r7800 firmware< 1.0.2.80nvdUScpe:2.3:o:netgear:r7800_firmware:*:*:*:*:*:*:*:*
netgear r8900 firmware< 1.0.5.28nvdUScpe:2.3:o:netgear:r8900_firmware:*:*:*:*:*:*:*:*
netgear r9000 firmware< 1.0.5.28nvdUScpe:2.3:o:netgear:r9000_firmware:*:*:*:*:*:*:*:*

showing 20 of 44

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2021-04-14modified 2026-06-17

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+16123 more

references (7)

External citations — patches, advisories, analysis.

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