How severe is CVE-2023-3959?

CVE-2023-3959 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-2023-3959 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 40% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-3959?

CVE-2023-3959 primarily affects Zavio Cf7500 Firmware. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-3959?

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-2023-3959 published?

CVE-2023-3959 was published on 2023-11-08 and last updated on 2026-06-17.

CVE-2023-3959

CVE-2023-3959 is a critical-severity vulnerability in Zavio Cf7500 Firmware with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 40% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-787.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 40% (98th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Zavio Cf7500 Firmware
Published: 2023-11-08
Last modified: 2026-06-17

Description

Zavio CF7500, CF7300, CF7201, CF7501, CB3211, CB3212, CB5220, CB6231, B8520, B8220, and CD321 IP Cameras with firmware version M2.1.6.05 are vulnerable to multiple instances of stack-based overflows. While processing XML elements from incoming network requests, the product does not sufficiently check or validate allocated buffer size. This may lead to remote code execution.

Frequently asked questions

What is CVE-2023-3959?: Zavio CF7500, CF7300, CF7201, CF7501, CB3211, CB3212, CB5220, CB6231, B8520, B8220, and CD321 IP Cameras with firmware version M2.1.6.05 are vulnerable to multiple instances of stack-based overflows. While processing XML elements from incoming network requests, the product does not sufficiently check or validate allocated buffer size. This may lead to remote code execution.
How severe is CVE-2023-3959?: CVE-2023-3959 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-2023-3959 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 40% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-3959?: CVE-2023-3959 primarily affects Zavio Cf7500 Firmware. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-3959?: 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-2023-3959 published?: CVE-2023-3959 was published on 2023-11-08 and last updated on 2026-06-17.

References

https://www.cisa.gov/news-events/ics-advisories/icsa-23-304-03

Affected products (11)

cpe:2.3:o:zavio:cf7500_firmware:m2.1.6.05:*:*:*:*:*:*:*
cpe:2.3:o:zavio:cf7300_firmware:m2.1.6.05:*:*:*:*:*:*:*
cpe:2.3:o:zavio:cf7201_firmware:m2.1.6.05:*:*:*:*:*:*:*
cpe:2.3:o:zavio:cf7501_firmware:m2.1.6.05:*:*:*:*:*:*:*
cpe:2.3:o:zavio:cb3211_firmware:m2.1.6.05:*:*:*:*:*:*:*
cpe:2.3:o:zavio:cb3212_firmware:m2.1.6.05:*:*:*:*:*:*:*
cpe:2.3:o:zavio:cb5220_firmware:m2.1.6.05:*:*:*:*:*:*:*
cpe:2.3:o:zavio:cb6231_firmware:m2.1.6.05:*:*:*:*:*:*:*
cpe:2.3:o:zavio:b8520_firmware:m2.1.6.05:*:*:*:*:*:*:*
cpe:2.3:o:zavio:b8220_firmware:m2.1.6.05:*:*:*:*:*:*:*
cpe:2.3:o:zavio:cd321_firmware:m2.1.6.05:*:*:*:*:*:*:*

More vulnerabilities in Zavio Cf7500 Firmware

CVE-2023-45225 — Critical (CVSS 9.8): Zavio CF7500, CF7300, CF7201, CF7501, CB3211, CB3212, CB5220, CB6231, B8520, B8220, and CD321 IP Cameras with…
CVE-2023-43755 — Critical (CVSS 9.8): Zavio CF7500, CF7300, CF7201, CF7501, CB3211, CB3212, CB5220, CB6231, B8520, B8220, and CD321 IP Cameras with…
CVE-2023-4249 — High (CVSS 8.8): Zavio CF7500, CF7300, CF7201, CF7501, CB3211, CB3212, CB5220, CB6231, B8520, B8220, and CD321 IP Cameras with…
CVE-2023-39435 — High (CVSS 8.8): Zavio CF7500, CF7300, CF7201, CF7501, CB3211, CB3212, CB5220, CB6231, B8520, B8220, and CD321 IP Cameras with…

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