Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HSummary
CVE-2023-28771 is a critical-severity OS Command Injection (CWE-78) vulnerability in Zyxel Zywall Usg 310 Firmware. Its CVSS base score is 9.8 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked in the top 0.1% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities 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.
CVE-2023-28771 is an improper error message handling flaw, tracked as CWE-78, that affects multiple Zyxel firewall product lines. Impacted devices include the ZyWALL/USG series running firmware 4.60 through 4.73, and the VPN, USG FLEX, and ATP series running firmware 4.60 through 5.35. The vulnerability permits unauthenticated remote code execution with a CVSS 3.1 score of 9.8.
An unauthenticated attacker can exploit the issue by sending specially crafted IKE packets to an exposed device, resulting in arbitrary OS command execution with full system privileges and no user interaction required.
Zyxel’s security advisory recommends immediate firmware upgrades to patched releases and, where upgrades are not feasible, applying the vendor-supplied workarounds. The flaw appears in CISA’s Known Exploited Vulnerabilities catalog, and its EPSS score has reached 0.9435, indicating active exploitation interest following disclosure.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-32406
Vulnerability Data
Improper error message handling in Zyxel ZyWALL/USG series firmware versions 4.60 through 4.73, VPN series firmware versions 4.60 through 5.35, USG FLEX series firmware versions 4.60 through 5.35, and ATP series firmware versions 4.60 through 5.35, which could allow an…
more
unauthenticated attacker to execute some OS commands remotely by sending crafted packets to an affected device.
- CWE(s)
- KEV Date Added
- 31 May 2023
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
—
—
—
V1.2.5V1.2.8V15.2.5
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.
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.
PR.PS-06's SDLC practices directly require secure coding and input handling that blocks command-injection defects, yet the single broad outcome leaves many specific neutralization vectors and verification gaps unaddressed.
Routine patching/maintenance can remediate known command-injection CVEs in dependencies (partial forward) but does nothing to stop developers from introducing improper neutralization in custom code (none reverse).
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.
Security testing and code review target insecure use of operating-system command interfaces, catching command-injection flaws introduced during development.