Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2023-43239 is a critical-severity Out-of-bounds Write (CWE-787) vulnerability in Dlink Dir-816 A2 Firmware. Its CVSS base score is 9.8 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Security Account Manager (T1003.002); ranked in the top 4% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
D-Link DIR-816 A2 firmware version 1.10CNB05 contains a stack-based buffer overflow vulnerability (CWE-121, CWE-787) triggered by the flag_5G parameter in the showMACfilterMAC function. The flaw permits an out-of-bounds write on the stack when the device processes a crafted HTTP request to its web management interface.
Unauthenticated attackers with network access can send a malicious request that overflows the stack, leading to remote code execution, denial of service, or full device compromise. The vulnerability carries a CVSS 3.1 score of 9.8, reflecting that no authentication or user interaction is required and the attack can be performed remotely with low complexity.
Public references include a detailed proof-of-concept on GitHub and D-Link’s security bulletin page, which lists affected hardware and directs users to firmware updates or configuration guidance. The EPSS score has reached a peak of 0.6064 with a current value of 0.5799, indicating sustained exploitation interest after disclosure.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-47658
Vulnerability Data
D-Link DIR-816 A2 v1.10CNB05 was discovered to contain a stack overflow via parameter flag_5G in showMACfilterMAC.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 2 hardening rules · 2 OS baselines
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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.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Vulnerability scanning and recording can discover out-of-bounds write flaws so they can be remediated.
Patching or replacing vulnerable software directly eliminates known instances of this coding weakness.
Secure-development practices (static analysis, bounds checking, code review) are the primary means of preventing out-of-bounds writes.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Hardening callouts derived
Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (higher-evidence rows only; rows rated `none` are excluded).
Oracle Linux 8 (1 rule)
- V-248594 OL 8 must implement address space layout randomization (ASLR) to protect its memory from unauthorized code execution. blocks CWE-121
Oracle Linux 9 (1 rule)
- V-271452 OL 9 must use a Linux Security Module configured to enforce limits on system services. blocks CWE-121