CVE-2026-2120
Published: 08 February 2026
Summary
CVE-2026-2120 is a high-severity Command Injection (CWE-77) vulnerability in Dlink Dir-823X Firmware. Its CVSS base score is 7.3 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Unix Shell (T1059.004); ranked in the top 26.5% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and AC-6 (Least Privilege).
Deeper analysis
CVE-2026-2120 is an OS command injection vulnerability (CWE-77, CWE-78) in the D-Link DIR-823X router running firmware version 250416. The issue affects an unknown function in the /goform/set_server_settings file within the Configuration Parameter Handler component. It is triggered by manipulating the terminal_addr, server_ip, or server_port arguments, allowing remote exploitation.
The vulnerability carries a CVSS v3.1 base score of 7.2 (AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H). Remote attackers with high privileges, such as authenticated administrative users, can exploit it with low complexity and no user interaction. Successful exploitation enables arbitrary OS command execution, resulting in high impacts to confidentiality, integrity, and availability, potentially leading to full device compromise.
Advisories from VulDB, including entries at https://vuldb.com/?ctiid.344694, https://vuldb.com/?id.344694, and https://vuldb.com/?submit.746916, document the vulnerability. The D-Link website (https://www.dlink.com/) is referenced for potential firmware updates or further guidance. A public exploit is available via a GitHub issue at https://github.com/master-abc/cve/issues/26 and might be used in attacks.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-5826
Vulnerability details
A vulnerability was identified in D-Link DIR-823X 250416. This affects an unknown function of the file /goform/set_server_settings of the component Configuration Parameter Handler. The manipulation of the argument terminal_addr/server_ip/server_port leads to os command injection. The attack may be initiated remotely.…
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The exploit is publicly available and might be used.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
OS command injection (CWE-78) directly enables arbitrary Unix shell command execution on the router firmware via manipulated configuration parameters.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Validates terminal_addr, server_ip and server_port inputs before they reach the Configuration Parameter Handler, directly blocking OS command injection.
Limits the number of accounts granted the high-privilege rights required to invoke /goform/set_server_settings.
Disables or restricts the vulnerable configuration interface and parameters that accept untrusted terminal_addr/server values.