CVE-2019-9590: An issue was discovered on TENGCONTROL T-920 PLC v5.5 devices

This week

HIGH 7.5REMOTEMITIGATE

CVE-2019-9590 is a high-severity flaw (CVSS 7.5) affecting t-920 plc firmware. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

An issue was discovered on TENGCONTROL T-920 PLC v5.5 devices. It allows remote attackers to cause a denial of service (persistent failure mode) by sending a series of \x19\xb2\x00\x00\x00\x06\x43\x01\x00\xac\xff\x00 (aka UID 0x43) requests to TCP port 502.

Why this priority

High severity
Public exploit reference
Remotely exploitable, no login, no user action

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	7.5 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	1.8% (top 21%)
CISA exploited list	No
Published	2019-03-06
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: tengcon

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2019-03-06 16:29 UTCPublished CVE record published
2026-06-17 02:44 UTCUpdated Record last modified

tengcon t-920 plc firmware MITIGATE

Affected: 5.5

Fixed in: no fixed release known

Safe to downgrade to: a release before 5.5

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2019-9590?

t-920 plc firmware: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2019-9590 being exploited?

CVE-2019-9590 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2019-9590 affect?

CVE-2019-9590 affects t-920 plc firmware. Severity is high (CVSS 7.5). An issue was discovered on TENGCONTROL T-920 PLC v5.5 devices. It allows remote attackers to cause a denial of service (persistent failure mode) by sending a series of \x19\xb2\x00\x00\x00\x06\x43\x01\x00\xac\xff\x00 (aka UID 0x43) requests

How urgent is CVE-2019-9590?

Priority 56/100. High severity; Public exploit reference; Remotely exploitable, no login, no user action

References

← Back to latest CVEs