{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata — refreshed continuously.","feed_url":"https://feed.craftedsignal.io/tags/cve-2026-21765/","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cves":[{"cvss":8.8,"id":"CVE-2026-21765"}],"_cs_exploited":false,"_cs_products":[],"_cs_severities":["high"],"_cs_tags":["cve-2026-21765","privilege-escalation","windows","hcl-bigfix"],"_cs_type":"advisory","_cs_vendors":[],"content_html":"\u003cp\u003eHCL BigFix Platform is affected by insecure permissions on private cryptographic keys. This vulnerability, identified as CVE-2026-21765, exists because private cryptographic keys located on Windows host machines may have overly permissive file system permissions. This could allow unauthorized users or processes to access sensitive cryptographic material, potentially leading to privilege escalation or other malicious activities within the BigFix environment. Successful exploitation of this vulnerability could allow attackers to decrypt sensitive data or impersonate legitimate components of the BigFix platform. Defenders should ensure proper file system permissions are enforced on sensitive cryptographic key files within the HCL BigFix installation directory.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAttacker gains initial access to a Windows host machine running the HCL BigFix client or server component. This could be achieved through existing malware infections, compromised credentials, or exploitation of other vulnerabilities.\u003c/li\u003e\n\u003cli\u003eAttacker identifies the location of the private cryptographic key files used by HCL BigFix. The specific location may vary depending on the BigFix configuration, but is typically within the BigFix installation directory.\u003c/li\u003e\n\u003cli\u003eAttacker checks the file system permissions of the cryptographic key files. Due to the vulnerability, these permissions may be overly permissive, granting read or write access to unauthorized users or groups.\u003c/li\u003e\n\u003cli\u003eAttacker copies the private cryptographic key files to a location where they can be further analyzed or used.\u003c/li\u003e\n\u003cli\u003eAttacker uses the stolen private keys to decrypt sensitive data stored or transmitted by the BigFix platform. This could include configuration settings, credentials, or other confidential information.\u003c/li\u003e\n\u003cli\u003eAttacker uses the stolen private keys to impersonate legitimate BigFix components, such as the client or server.\u003c/li\u003e\n\u003cli\u003eAttacker elevates privileges within the BigFix environment by using the impersonated identity to execute commands or access restricted resources.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation of CVE-2026-21765 could allow an attacker to gain unauthorized access to sensitive data, escalate privileges within the HCL BigFix environment, and potentially compromise the entire BigFix deployment. The vulnerability affects any organization using HCL BigFix on Windows. If exploited successfully, attackers could gain complete control over managed endpoints.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eApply the patch or mitigation steps provided by HCL Software as described in \u003ca href=\"https://support.hcl-software.com/csm?id=kb_article\u0026amp;sysparm_article=KB0129906\"\u003eKB0129906\u003c/a\u003e to correct the file system permissions on the private cryptographic key files.\u003c/li\u003e\n\u003cli\u003eUse the Sigma rule \u0026ldquo;Detect Suspicious Access to HCL BigFix Private Keys\u0026rdquo; to detect unauthorized access attempts to the affected key files.\u003c/li\u003e\n\u003cli\u003eMonitor file system access logs on Windows hosts running HCL BigFix components for suspicious activity targeting cryptographic key files.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-04-02T00:16:23Z","date_published":"2026-04-02T00:16:23Z","id":"/briefs/2026-04-hcl-bigfix-privilege-escalation/","summary":"HCL BigFix Platform is vulnerable to insecure permissions on private cryptographic keys, where keys on a Windows host may have overly permissive file system permissions, potentially leading to unauthorized access and privilege escalation.","title":"HCL BigFix Platform Insecure Permissions Vulnerability (CVE-2026-21765)","url":"https://feed.craftedsignal.io/briefs/2026-04-hcl-bigfix-privilege-escalation/"}],"language":"en","title":"CraftedSignal Threat Feed — Cve-2026-21765","version":"https://jsonfeed.org/version/1.1"}