CVE-2026-5312
Published: 01 April 2026
Summary
CVE-2026-5312 is a medium-severity Incorrect Privilege Assignment (CWE-266) vulnerability in Dlink Dns-1550-04 Firmware. Its CVSS base score is 5.5 (Medium).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 42.1th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-18069
Vulnerability details
A weakness has been identified in D-Link DNS-120, DNR-202L, DNS-315L, DNS-320, DNS-320L, DNS-320LW, DNS-321, DNR-322L, DNS-323, DNS-325, DNS-326, DNS-327L, DNR-326, DNS-340L, DNS-343, DNS-345, DNS-726-4, DNS-1100-4, DNS-1200-05 and DNS-1550-04 up to 20260205. Affected by this vulnerability is the function FMT_restart/Status_HDInfo/SMART_List/ScanDisk_info/ScanDisk/volume_status/Get_Volume_Mapping/FMT_check_disk_remount_state/FMT_rebuildinfo/FMT_result_list/FMT_result_list_phy/FMT_get_dminfo/FMT_manually_rebuild_info/Get_current_raidtype of…
more
the file /cgi-bin/dsk_mgr.cgi. Executing a manipulation can lead to improper access controls. It is possible to launch the attack remotely. The exploit has been made available to the public and could be used for attacks.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Remote exploitation of public-facing NAS web CGI (dsk_mgr.cgi) due to improper access controls (CWE-284/266) directly enables T1190 and facilitates privilege escalation via T1068.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
The access control policy and procedures directly mandate and enforce proper access control mechanisms across the organization.
Supervision and review of access control activities directly detects and remediates improper access configurations or usages.
Defining account types, requiring approvals for creation, specifying authorizations, monitoring usage, and reviewing accounts directly prevents improper access control by ensuring only authorized accounts exist and are used.
The control requires explicit definition of separated access authorizations, making incorrect privilege assignments that bundle conflicting duties harder to implement.
Ensures privileges are assigned only as necessary rather than incorrectly over-granted.
Device lock enforces restricted access until re-authentication, directly reducing unauthorized use of active sessions.
Explicitly identifying and documenting actions permitted without identification or authentication enforces proper access control boundaries by defining justified exceptions.
By automatically labeling outputs with security attributes, the control supports attribute-based enforcement and reduces exploitability of improper access control weaknesses.