Vulnerability report

Active exploitation observed Confirmed confidence Not in CISA KEV

CVE-2019-19824

Realtek SDK based routers

TOTOLINK / Realtek SDK based routers · 0 to <= 2.0.0

Watch CVE-2019-19824 Browse KEV feed
Severity
CVSS 8.8 · High
Confidence
Confirmed
Exploit status
Observed in sensors
EPSS
25.1%
First observed
03 Jul 2026
Last observed
11 Oct 2026

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2019-19824 is a vulnerability affecting TOTOLINK Realtek SDK based routers. On certain TOTOLINK Realtek SDK based routers, an authenticated attacker may execute arbitrary OS commands via the sysCmd parameter to...

Is it exploited?

Yes. Previdian sensors observed exploitation attempts with confirmed confidence. Also confirmed by third-party sources.

Who is affected?

TOTOLINK / Realtek SDK based routers 0 to <= 2.0.0.

What should we do?

Patch immediately, validate internet-facing exposure, and monitor for matching requests.

Overview

Realtek SDK based routers

On certain TOTOLINK Realtek SDK based routers, an authenticated attacker may execute arbitrary OS commands via the sysCmd parameter to the boafrm/formSysCmd URI, even if the GUI (syscmd.htm) is not available. This allows for full control over the device's internals.

This affects A3002RU through 2.0.0, A702R through 2.1.3, N301RT through 2.1.6, N302R through 3.4.0, N300RT through 3.4.0, N200RE through 4.0.0, N150RT through 3.4.0, N100RE through 3.4.0, and N302RE 2.0.2.

totolink Affected
a3002ru_firmware
Through 2.0.0
totolink Affected
a702r_firmware
Through 2.1.3
totolink Affected
n301rt_firmware
Through 2.1.6
totolink Affected
n302r_firmware
Through 3.4.0
totolink Affected
n200re_firmware
Through 4.0.0
totolink Affected
n150rt_firmware
Through 3.4.0
totolink Affected
n100re_firmware
Through 3.4.0
totolink Affected
n302re_firmware
Before 2.0.2
Published
27 Jan 2020
Exploitation Reported
25 Apr 2025
Attack vector
Remote
Complexity
Low
Privileges
Low
User interaction
None

Tags

edge nuclei_scanner

CVE References

Exploitation evidence

Why Previdian marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

The Shadowserver

Recorded 25 Apr 2025

A trusted third party reported exploitation.

Active exploitation observed

Previdian sensor

First observed 03 Jul 2026

Previdian first observed exploitation attempts targeting this vulnerability in our honeypot sensors.

Proof of concept available

Nuclei Templates

Recorded 12 Jun 2026

Public scanner or PoC coverage increases practical exploitability.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the Previdian Pro API.

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Source Added
The Shadowserver First 2025-04-25 00:00 UTC
Previdian Sensors 2026-07-30 14:56 UTC

Operational indicators for this CVE are listed under Detection.

Sensor telemetry

First-party evidence of exploitation activity

Previdian sensors recorded exploitation attempts targeting this vulnerability. The cards and chart show volume, unique attackers, and daily activity.

30

Attempts observed

16

Unique attacker IPs

11

Attacker countries

BG · CH · FI · FR · HK · IN · JP · NL · SC · US · YE

18

Sensors observed

CVE-2019-19824 exploitation attempts over the last 87 days

Daily events observed by Previdian sensors

Updated 12 Oct 2026

0
2
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2
0
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0
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0
0
0
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0
0
0
1
0
1
0
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1
0
0
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1
0
0
0
0
0
0
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1
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3
1
1
0
18 Jul 5 Aug 23 Aug 10 Sep 12 Oct

First observed 03 Jul 2026 · Last observed 11 Oct 2026

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Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
User-Agents
Callback hosts
2
16
2

Request targets and User-Agents available in Pro. Callback host details available in Enterprise.

Virtual patch status

Previdian virtual patch guidance is available for this CVE.

AWS WAF Cloudflare ModSecurity

Attacker IP Indicators

Attacker IP indicators observed · available in Pro and Enterprise.

Sensor-derived attacker IP indicators are available to Pro and Enterprise accounts under Detection and through the Pro API.

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Scanner Artifacts

Scanner and exploit-framework references linked to this CVE.

Scanner Reference Detected
Nuclei https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2019/CVE-2019-19824.yaml 25 Apr 2025

Virtual Patch Detail

Compensating WAF rules for this CVE.

Available

Enterprise feature. Virtual patch rule content and deployable vendor exports (ModSecurity, Cloudflare, AWS WAF) are available to Previdian Enterprise users.

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Risk and context

Severity, weaknesses, and research context

CVSS v3.1

8.8 High

Potential damage if exploited. Separate from whether attackers are using it.

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS

25.1%

Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.

Weaknesses

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') CWE-78

All CVSS Scores

CVSS v3.1 8.8 High

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS v2.0 9.0 High

AV:N/AC:L/Au:S/C:C/I:C/A:C

Potential Proof of Concepts

These PoCs are unverified and could contain malware. Use at your own risk.

TOTOLINK Realtek SD Routers - Remote Command Injection

nuclei · Created Unknown

Timeline

From disclosure to observed exploitation

  1. 13:00 UTC

    Virtual patch available

    Compensating WAF rule available to block exploitation

  2. 04:21 UTC

    Indicators of compromise added (23)

    Indicators of compromise recorded

  3. 04:21 UTC

    Observed by Previdian sensors

    Evidence-backed exploitation signal

  4. 14:20 UTC

    Public PoC available

    Public proof-of-concept code published

  5. 00:00 UTC

    Added to Previdian KEV Feed

    High-confidence, third-party attested exploitation

  6. 00:00 UTC

    Nuclei template available

    Scanner coverage available

  7. 17:03 UTC

    CVE published

    Vulnerability disclosed publicly

  8. 00:00 UTC

    CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

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  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2019-19824

Free JSON includes basic KEV fields 
{
  "cve_id": "CVE-2019-19824",
  "confidence": "Confirmed",
  "cvss_score": 8.8,
  "cvss_estimated": false,
  "epss_score": 0.25135,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": true
  },
  "sensor_telemetry": { "attempts": 30, "sensors": 18 }
}