CVE-2021-34947 json
NETGEAR R7800 net-cgi Out-Of-Bounds Write Remote Code Execution Vulnerability
published 2024-05-07 2 y ago modified 2026-06-17 4 mo ago also EUVD-2021-21594
- cvss
- 8.8
- version 3.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 46%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- netgear d7800_firmware 1.0.1.64
- netgear ex2700_firmware 1.0.1.66
- netgear ex6100_firmware 1.0.1.106
- netgear ex6150_firmware 1.0.1.106
- netgear ex6200_firmware 1.0.1.86
- netgear ex6250_firmware 1.0.0.146
- netgear ex6400_firmware 1.0.2.164
- netgear ex6400v2_firmware 1.0.0.146
- netgear ex6410_firmware 1.0.0.146
- netgear ex6420_firmware 1.0.0.146
- netgear ex6500v1_firmware 1.0.0.146
- netgear ex7300_firmware 1.0.2.164
- netgear ex7300v2_firmware 1.0.0.146
- netgear ex7320_firmware 1.0.0.146
- netgear ex7700_firmware 1.0.0.222
- netgear ex8000_firmware 1.0.1.238
- netgear lbr1020_firmware 2.6.5.32
- netgear lbr20_firmware 2.6.5.32
- netgear r6700ax_firmware 1.0.5.108
- netgear r7800_firmware 1.0.2.84
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 2 y ago
Exploit prediction
0.55% chance of exploitation in the next 30 days, higher than 46% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.0 | 8.8 | CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Affected products
- NETGEAR R7800
Classification
- Weakness
-
- CWE-787 Out-of-bounds Write
References
-
kb.netgear.com
/000064044/Security-Advisory-for-Pre-Authentication-Buffer-Overflow-on-Some-Routers-PSV-2021-0129
vendor-advisory, third-party-advisory
-
zerodayinitiative.com
/advisories/ZDI-21-1116/
third-party-advisory
Sources
- CVE List CVE-2021-34947
- NVD CVE-2021-34947
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