إرسال #751633: Beetel 777VR1 Firmware Versions: V01.00.09 / V01.00.09_55 Obsolete and Cryptographically Broken SSH Protocols CWE-327

Use of Obsolete and Cryptographically Broken SSH Protocols and Algorithms Leading to Credential Disclosure and Session Compromise
Affected Product

Product: Beetel 777VR1 Broadband Router

Firmware Versions: V01.00.09 / V01.00.09_55
Vulnerability Classification

CWE-327 – Use of a Broken or Risky Cryptographic Algorithm (Primary)
CWE-326 – Inadequate Encryption Strength
CWE-310 – Cryptographic Issues
CWE-522 – Insufficiently Protected Credentials
CWE-295 – Improper Certificate Validation

Vulnerability Description

A critical cryptographic vulnerability exists in the SSH service implemented in the Beetel 777VR1 Broadband Router firmware versions V01.00.09 and V01.00.09_55 due to the use of obsolete SSH protocol versions and cryptographically broken algorithms.

The router’s SSH daemon identifies itself as SSH_0.48, an extremely outdated implementation dating back to approximately 2006, despite the firmware having a very recent date and year of build (Nov 7, 2019). This version predates modern SSH security hardening and supports only deprecated key exchange mechanisms, host key algorithms, and ciphers that are no longer considered secure.

Specifically, the SSH service enforces the use of weak cryptographic primitives such as diffie-hellman-group1-sha1, ssh-rsa with SHA-1, and 3des-cbc. These algorithms have been formally deprecated due to known cryptographic weaknesses and are disabled by default in modern SSH clients.

As a result, SSH sessions established with the router lack confidentiality, integrity, and resistance to active or passive attacks. Network attackers can exploit these weaknesses to intercept credentials, perform man-in-the-middle attacks, or decrypt SSH traffic.
Cryptographic Weakness Details

The SSH service exhibits the following critical weaknesses:

Obsolete SSH protocol implementation
Server version: SSH_0.48

Broken key exchange
diffie-hellman-group1-sha1 (768-bit MODP group)

Weak host key algorithms
ssh-rsa using SHA-1

Insecure symmetric cipher
3des-cbc (64-bit block size, vulnerable to Sweet32)

These cryptographic mechanisms are mathematically broken or deprecated and violate modern security standards including NIST, CIS Benchmarks, and RFC recommendations.
Security Implications

Because of these cryptographic weaknesses:

SSH authentication credentials can be intercepted
SSH sessions can be decrypted offline
Man-in-the-middle attacks can be performed without detection
Session integrity cannot be guaranteed
Attackers can downgrade or manipulate cryptographic negotiation

When combined with weak or reused credentials, these issues significantly amplify the risk of full device compromise.
Impact

Disclosure of SSH authentication credentials
Man-in-the-middle attacks against management sessions
Decryption of SSH traffic
Loss of confidentiality and integrity
Increased likelihood of full administrative compromise

Attack Vector

Network-based attacker
LAN or WAN (as SSH is exposed)
Passive or active interception

Severity

Critical

Proof / Steps to Reproduce

Please see detailed writeup at the github gist link below:
https://gist.github.com/raghav20232023/8e8e559f80e2d596cb6154747f69a081

Mitigation

Remove obsolete SSH implementations entirely

Upgrade to a modern, maintained SSH server, as and when the cryptographic algorithm is no longer secure.

Disable all deprecated algorithms, including:
diffie-hellman-group1-sha1
ssh-rsa (SHA-1)
3des-cbc

Enforce modern cryptographic standards:
Strong key exchange (e.g., ECDH / Curve25519)
Strong ciphers (AES-GCM / ChaCha20-Poly1305)
Modern host keys (ED25519 / RSA-SHA2)

Enforce secure credential policies and key-based authentication

Note to CNA (VulDB)

This vulnerability is distinct from the SSH service exposure / activation vulnerability reported separately for the same device.

This issue specifically concerns the use of obsolete and cryptographically broken SSH protocols and algorithms (SSH_0.48, diffie-hellman-group1-sha1, ssh-rsa with SHA-1, 3des-cbc) after the SSH service is reachable, regardless of how that reachability occurs.

The cryptographic weakness exists independently of the service exposure mechanism and would remain exploitable even if SSH were intentionally enabled by an administrator or exposed through misconfiguration. Conversely, the SSH service exposure vulnerability focuses on improper access control and unauthorized activation, not cryptographic design.

These issues represent separate root causes and should be tracked as distinct vulnerabilities.
Author and Credit

RAGHAV AGRAWAL

• المصدر: ⚠️ https://gist.github.com/raghav20232023/8e8e559f80e2d596cb6154747f69a081
• المستخدم: raghav_2026 (UID 94388)
• ارسال: 03/02/2026 10:43 PM (4 أشهر منذ)
• الاعتدال: 17/02/2026 08:01 AM (13 days later)
• الحالة: تمت الموافقة
• إدخال VulDB: 346268 [Beetel 777VR1 حتى 01.00.09 SSH Service تشفير ضعيف]
• النقاط: 20