How severe is CVE-2023-33239?

CVE-2023-33239 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-33239 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-33239?

CVE-2023-33239 primarily affects Moxa Tn-5900 Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-33239?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2023-33239 published?

CVE-2023-33239 was published on 2023-08-17 and last updated on 2026-06-17.

CVE-2023-33239

CVE-2023-33239 is a high-severity vulnerability in Moxa Tn-5900 Firmware with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-77.

Key facts

Severity: High (CVSS 3.x base score 8.8)
EPSS exploit prediction: 1% (63rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-77
Affected product: Moxa Tn-5900 Firmware
Published: 2023-08-17
Last modified: 2026-06-17

Description

TN-4900 Series firmware versions v1.2.4 and prior and TN-5900 Series firmware versions v3.3 and prior are vulnerable to the command injection vulnerability. This vulnerability stems from insufficient input validation in the key-generation function, which could potentially allow malicious users to execute remote code on affected devices.

Frequently asked questions

What is CVE-2023-33239?: TN-4900 Series firmware versions v1.2.4 and prior and TN-5900 Series firmware versions v3.3 and prior are vulnerable to the command injection vulnerability. This vulnerability stems from insufficient input validation in the key-generation function, which could potentially allow malicious users to execute remote code on affected devices.
How severe is CVE-2023-33239?: CVE-2023-33239 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-33239 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-33239?: CVE-2023-33239 primarily affects Moxa Tn-5900 Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-33239?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2023-33239 published?: CVE-2023-33239 was published on 2023-08-17 and last updated on 2026-06-17.

References

https://www.moxa.com/en/support/product-support/security-advisory/mpsa-230402-tn-5900-and-tn-4900-series-web-server-multiple-vulnerabilities

Affected products (2)

cpe:2.3:o:moxa:tn-5900_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:moxa:tn-4900_firmware:*:*:*:*:*:*:*:*

More vulnerabilities in Moxa Tn-5900 Firmware

CVE-2021-46560 — Critical (CVSS 9.8): The firmware on Moxa TN-5900 devices through 3.1 allows command injection that could lead to device damage.
CVE-2023-34213 — High (CVSS 8.8): TN-5900 Series firmware versions v3.3 and prior are vulnerable to command-injection vulnerability. This vulnerability…
CVE-2023-33237 — High (CVSS 8.8): TN-5900 Series firmware version v3.3 and prior is vulnerable to improper-authentication vulnerability. This…
CVE-2023-34217 — High (CVSS 8.1): TN-4900 Series firmware versions v1.2.4 and prior and TN-5900 Series firmware versions v3.3 and prior are vulnerable to…
CVE-2023-34216 — High (CVSS 8.1): TN-4900 Series firmware versions v1.2.4 and prior and TN-5900 Series firmware versions v3.3 and prior are vulnerable to…
CVE-2021-46559 — High (CVSS 7.5): The firmware on Moxa TN-5900 devices through 3.1 has a weak algorithm that allows an attacker to defeat an inspection…

All CVEs affecting Moxa Tn-5900 Firmware →

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