Cyber Posture

CVE-2026-28777

CriticalPublic PoC

Published: 04 March 2026

Published
04 March 2026
Modified
17 March 2026
KEV Added
Patch
CVSS Score 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0043 63.1th percentile
Risk Priority 20 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-28777 is a critical-severity Use of Hard-coded Credentials (CWE-798) vulnerability in Datacast Sfx2100 Firmware. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique External Remote Services (T1133); ranked in the top 36.9% 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 AC-17 (Remote Access) and AC-2 (Account Management).

Threat & Defense at a Glance

What attackers do: exploitation maps to External Remote Services (T1133) and 1 other technique. What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

IA-5 requires management of authenticators prohibiting hard-coded credentials and enforcing strong passwords, directly preventing exploitation of the trivial password for the 'user' account.

prevent

AC-2 mandates account management processes to disable unnecessary accounts or change default weak credentials like the 'user' account, blocking unauthorized access.

prevent

AC-17 establishes controls for remote access including authorization and protection of methods like SSH, mitigating remote unauthenticated exploitation.

MITRE ATT&CK Enterprise TechniquesAI

T1133 External Remote Services Persistence
Adversaries may leverage external-facing remote services to initially access and/or persist within a network.
T1078.001 Default Accounts Stealth
Adversaries may obtain and abuse credentials of a default account as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.
Why these techniques?

The vulnerability involves hard-coded trivial credentials for a default 'user' account accessible via public-facing SSH, directly enabling initial access through external remote services (T1133) and use of default accounts (T1078.001).

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

NVD Description

International Datacasting Corporation (IDC) SFX2100 Satellite Receiver, trivial password for the `user` (usr) account. A remote unauthenticated attacker can exploit this to gain unauthorized SSH access to the system, while intially dropped into a restricted shell, an attacker can trivially…

more

spawn a complete pty to gain an appropriately interactive shell.

Deeper analysisAI

CVE-2026-28777 is a critical vulnerability in the International Datacasting Corporation (IDC) SFX2100 Satellite Receiver, stemming from a trivial password for the `user` (also denoted as `usr`) account. This issue, classified under CWE-798 (Use of Hard-coded Credentials), enables unauthorized access via SSH and carries a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), reflecting its high potential for confidentiality, integrity, and availability impacts.

A remote unauthenticated attacker can exploit this vulnerability by connecting to the device's SSH service using the known trivial password for the `user` account. This grants initial access to a restricted shell, from which the attacker can trivially spawn a complete pseudo-terminal (PTY) to achieve a fully interactive shell on the system.

Mitigation guidance and additional details are available in the referenced advisory at https://www.abdulmhsblog.com/posts/sfx2100-vulns/. No vendor patches or specific remediation steps are outlined in the CVE description.

Details

CWE(s)

Affected Products

datacast
sfx2100 firmware
all versions

CVEs Like This One

CVE-2026-28776Same product: Datacast Sfx2100
CVE-2026-29119Same product: Datacast Sfx2100
CVE-2026-28778Same product: Datacast Sfx2100
CVE-2026-29120Same product: Datacast Sfx2100
CVE-2026-29128Same product: Datacast Sfx2100
CVE-2026-29126Same product: Datacast Sfx2100
CVE-2026-28775Same product: Datacast Sfx2100
CVE-2026-28774Same product: Datacast Sfx2100
CVE-2026-29124Same product: Datacast Sfx2100
CVE-2026-29127Same product: Datacast Sfx2100

References