CVE-2021-27257 - CVE House
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Status published Medium CVE-2021-27257

This vulnerability allows network-adjacent attackers to compromise the integrity of...

Vulnerability Description

This vulnerability allows network-adjacent attackers to compromise the integrity of downloaded information on affected installations of NETGEAR R7800 firmware version 1.0.2.76. Authentication is not required to exploit this vulnerability. The specific flaw exists within the downloading of files via FTP. The issue results from the lack of proper validation of the certificate presented by the server. An attacker can leverage this in conjunction with other vulnerabilities to execute arbitrary code in the context of root. Was ZDI-CAN-12362.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • botto

References

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Affected Vendor

Affected Software

R7800
Vulnerable Versions:
firmware version 1.0.2.76

Timeline

Official Publish: March 5th, 2021
Last Modified: August 3rd, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Weaknesses (CWE)

CWE-295

MITRE ATT&CK TTPs

T1557 Adversary-in-the-Middle
Credential Access
T1040 Network Sniffing
Collection
T1552 Unsecured Credentials
Credential Access
T1071 Application Layer Protocol
Command and Control
T1565 Data Manipulation
Impact