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Fencer Intel
high 8.8

CVE-2021-31802 in the critical feed json

NETGEAR R7000 1.0.11.116 devices have a heap-based Buffer Overflow that is exploitable from the local network without authentication.

published 5y ago modified 4mo ago also EUVD-2021-18681

cvss
8.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
14.2%
EPSS 14.2% chance of exploitation in 30 days, percentile 96%
public exploits
1
Metasploit

Summary

NETGEAR R7000 1.0.11.116 devices have a heap-based Buffer Overflow that is exploitable from the local network without authentication. The vulnerability exists within the handling of an HTTP request. An attacker can leverage this to execute code as root. The problem is that a user-provided length value is trusted during a backup.cgi file upload. The attacker must add a \n before the Content-Length header.

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Timeline

  1. First public exploit (Metasploit auxiliary/admin/http/netgear_r7000_backup_cgi_heap_overflow_rce)
  2. Published

Exploit prediction

14.18% chance of exploitation in the next 30 days, higher than 96% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

CVSS scores

assigned by version score vector
NVD 3.1 8.8 CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 8.3 AV:A/AC:L/Au:N/C:C/I:C/A:C

Classification

Weakness

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.