CVE-2023-39435
Published: 08 November 2023
Summary
CVE-2023-39435 is a high-severity Stack-based Buffer Overflow (CWE-121) vulnerability in Zavio Cf7500 Firmware. Its CVSS base score is 8.8 (High).
Operationally, ranked in the top 43.0% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
Deeper analysis
Zavio IP cameras including the CF7500, CF7300, CF7201, CF7501, CB3211, CB3212, CB5220, CB6231, B8520, B8220, and CD321 models running firmware M2.1.6.05 contain a stack-based buffer overflow vulnerability. The flaw occurs when the devices process incoming network requests to update certain settings without properly validating or enforcing allocated buffer sizes, which can result in memory corruption. The issue is tracked under CWE-121 and CWE-787 and carries a CVSS 3.1 score of 8.8.
An attacker with low-privileged network access can send crafted requests that trigger the overflow, enabling remote code execution on the affected camera with impacts to confidentiality, integrity, and availability. No user interaction is required and the attack can be launched over the network.
CISA has published ICS advisory ICSA-23-304-03 addressing the affected Zavio devices. The EPSS score for this CVE rose sharply from a low baseline to a peak of 0.5954 on 2025-01-22 before receding to the current value of 0.0034, indicating a period of increased exploitation interest after disclosure.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-43159
Vulnerability details
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 stack-based overflows. During the process of updating certain settings sent from incoming network requests, the product does not…
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sufficiently check or validate allocated buffer size. This may lead to remote code execution.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Out-of-bounds writes that corrupt control flow or inject shellcode are rendered non-executable by the same memory protections.