Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:HSummary
CVE-2026-21765 is a high-severity Incorrect Default Permissions (CWE-276) vulnerability in Hcltech Bigfix Platform. Its CVSS base score is 8.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Credentials In Files (T1552.001); ranked at the 1th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and AC-6 (Least Privilege) — 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-2026-21765 affects the HCL BigFix Platform, specifically involving insecure permissions on private cryptographic keys located on Windows host machines. These keys are subject to overly permissive file system permissions, which could allow unauthorized access. The vulnerability is classified under CWE-276 (Incorrect Default Permissions) and CWE-732 (Incorrect Permission Assignment for Critical Resource), with a CVSS v3.1 base score of 8.8 (AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H), indicating high severity due to its potential for significant impact across confidentiality, integrity, and availability.
A local attacker with low privileges (PR:L) on the affected Windows host can exploit this vulnerability with low complexity and no user interaction required. Successful exploitation grants access to the private cryptographic keys, enabling high-impact outcomes such as data compromise (C:H), modification of systems or data (I:H), and disruption of services (A:H), particularly given the high scope (S:C) that allows influence beyond the vulnerable component.
The HCL Software support advisory at https://support.hcl-software.com/csm?id=kb_article&sysparm_article=KB0129906 provides details on mitigation, including recommended patches or configuration changes to secure the file system permissions on the private keys. Security practitioners should review this KB article for specific remediation steps applicable to their BigFix Platform deployments.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-18095
Vulnerability Data
HCL BigFix Platform is affected by insecure permissions on private cryptographic keys. The private cryptographic keys located on a Windows host machine might be subject to overly permissive file system permissions.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 18 hardening rules · 4 OS baselines
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Mitigating Controls (NIST 800-53 r5) AI
Enforces the access control policy that defines permissions on resources, thereby stopping incorrect assignments from remaining exploitable.
Requires least-privilege defaults so that installed files are not world-writable by default.
Requires documented, restrictive configuration settings that cover file and directory permissions.
Enforces access restrictions on changes, including permission settings applied during installation or configuration.
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.
Directly requires defining, enforcing, and reviewing access permissions and least privilege on resources.
Hardened baselines and configuration management explicitly require correct default file permissions.
Lifecycle management can encompass permission settings, yet the control is too broad to specifically mitigate incorrect defaults.
Secure SDLC practices include establishing secure defaults, but address only the development-phase portion of the weakness.
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 requiring owners to determine and document the exact permissions needed for each asset, the control reduces the likelihood that default or overly permissive file and resource permissions will be left in place.
Documented provisioning and revocation procedures reduce the chance that critical resources retain overly permissive default or leftover permissions after personnel changes.
Documented authorization, expiry rules, and audit logging of privileged accounts make it harder for critical resources to retain overly permissive or stale permission assignments.
Requiring explicit configuration of access controls and permissions for files, applications and services counters the assignment of overly permissive default or incorrect file-system rights.
Enforcing differentiated permissions on the source-code repository and program listings stops the assignment of overly broad default or inherited permissions to critical resources.
Standard templates that restrict access to utility programs and host parameter settings prevent the assignment of overly permissive default permissions on critical resources.
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` (authoritative rows only; rows rated `none` are excluded).
Oracle Linux 8 (1 rule)
- V-248577 OL 8 must enable kernel parameters to enforce Discretionary Access Control (DAC) on symlinks. prevents CWE-732
Windows Server 2016 (4 rules)
- V-224972 Active Directory Group Policy objects must have proper access control permissions. prevents CWE-732
- V-224833 Permissions for program file directories must conform to minimum requirements. prevents CWE-276
- V-224834 Permissions for the Windows installation directory must conform to minimum requirements. prevents CWE-276
Windows Server 2019 (4 rules)
- V-205741 Windows Server 2019 Active Directory Group Policy objects must have proper access control permissions. prevents CWE-732
- V-205735 Windows Server 2019 permissions for program file directories must conform to minimum requirements. prevents CWE-276
- V-205736 Windows Server 2019 permissions for the Windows installation directory must conform to minimum requirements. prevents CWE-276
Windows Server 2022 (4 rules)
- V-254393 Windows Server 2022 Active Directory Group Policy objects must have proper access control permissions. prevents CWE-732
- V-254252 Windows Server 2022 permissions for program file directories must conform to minimum requirements. prevents CWE-276
- V-254253 Windows Server 2022 permissions for the Windows installation directory must conform to minimum requirements. prevents CWE-276