How severe is CVE-2023-40039?

CVE-2023-40039 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-40039 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-40039?

CVE-2023-40039 primarily affects Arris Tg852g Firmware. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-40039?

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

When was CVE-2023-40039 published?

CVE-2023-40039 was published on 2023-09-11 and last updated on 2026-06-17.

CVE-2023-40039

CVE-2023-40039 is a critical-severity vulnerability in Arris Tg852g Firmware with a CVSS 3.x base score of 9.8. 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-284.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 1% (56th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-284
Affected product: Arris Tg852g Firmware
Published: 2023-09-11
Last modified: 2026-06-17

Description

An issue was discovered on ARRIS TG852G, TG862G, and TG1672G devices. A remote attacker (in proximity to a Wi-Fi network) can derive the default WPA2-PSK value by observing a beacon frame.

Frequently asked questions

What is CVE-2023-40039?: An issue was discovered on ARRIS TG852G, TG862G, and TG1672G devices. A remote attacker (in proximity to a Wi-Fi network) can derive the default WPA2-PSK value by observing a beacon frame.
How severe is CVE-2023-40039?: CVE-2023-40039 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-40039 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-40039?: CVE-2023-40039 primarily affects Arris Tg852g Firmware. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-40039?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2023-40039 published?: CVE-2023-40039 was published on 2023-09-11 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:o:arris:tg852g_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:arris:tg862g_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:arris:tg1672g_firmware:-:*:*:*:*:*:*:*

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