Raw vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XSummary
CVE-2016-20024 is a critical-severity Insertion of Sensitive Information into Externally-Accessible File or Directory (CWE-538) vulnerability in Cxsecurity (inferred from references). Its CVSS base score is 9.3 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Services File Permissions Weakness (T1574.010); ranked in the top 49% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and CM-5 (Access Restrictions for Change) — see the control section below for these in your framework.
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-2016-20024 is an insecure file permissions vulnerability (CWE-538) in ZKTeco ZKTime.Net 3.0.1.6. The ZKTimeNet3.0 directory and its contents feature world-writable permissions, enabling unprivileged users to modify executable files. This flaw allows replacement of legitimate executables with malicious binaries to achieve privilege escalation. The vulnerability carries a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H) and was published on 2026-03-16T14:17:48.350.
Attackers with unprivileged access can exploit the world-writable permissions on the ZKTimeNet3.0 directory to overwrite executable files with malicious versions. Successful exploitation leads to privilege escalation, potentially granting attackers higher-level access on the affected system. The CVSS vector indicates it is exploitable remotely by unauthenticated attackers with low complexity and no user interaction required.
Advisories and related resources, including exploit details, are available at https://cxsecurity.com/issue/WLB-2016080264, https://exchange.xforce.ibmcloud.com/vulnerabilities/116487, https://packetstormsecurity.com/files/138565, https://www.exploit-db.com/exploits/40322/, and https://www.vulncheck.com/advisories/zkteco-zktime-net-insecure-file-permissions-privilege-escalation.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2016-10803
Vulnerability Data
ZKTeco ZKTime.Net 3.0.1.6 contains an insecure file permissions vulnerability that allows unprivileged users to escalate privileges by modifying executable files. Attackers can exploit world-writable permissions on the ZKTimeNet3.0 directory and its contents to replace executable files with malicious binaries for…
more
privilege escalation.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
World-writable executable permissions directly enable file overwrite for local privilege escalation via T1044 (File System Permissions Weakness) and T1068 (Exploitation for Privilege Escalation).
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
Mitigating Controls (NIST 800-53 r5) AI
SC-34 prevents unauthorized modification of executable programs, directly mitigating the world-writable permissions that allow replacement of legitimate executables with malicious binaries.
CM-5 authorizes and restricts access to changes on system components such as the ZKTimeNet3.0 directory and its executable files, preventing unprivileged users from overwriting them.
AC-3 enforces approved access authorizations for system resources including files, ensuring unprivileged users cannot write to the vulnerable directory and executables.
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.
Least-privilege file and directory permissions directly prevent unauthorized actors from reading sensitive data placed in accessible locations.
Protecting data-at-rest encompasses file-level access controls and encryption that stop exposure of sensitive information in externally reachable paths.
Hardened configuration baselines and ongoing config management reduce the chance that sensitive data is written to world-readable files or directories.
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.
By ensuring that only the minimum necessary data is present in files or directories that may be reachable by external parties, the control lowers the impact of any subsequent exposure.
Requiring visible or metadata labels on classified information helps ensure that files placed in externally accessible locations still carry an explicit sensitivity marker, lowering the likelihood of unnoticed exposure.
The control’s requirement to remove or securely destroy information stored in externally accessible locations reduces the risk of sensitive data being left in files or directories that external parties can reach.
Logging disposals, selecting vetted external disposal services, and protecting media according to classification reduce the likelihood that sensitive information ends up in externally accessible files or directories.
Verifying and sanitizing equipment prior to disposal or resale prevents sensitive files or directories from remaining accessible to external parties who later obtain the hardware.