{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata — refreshed continuously.","feed_url":"https://feed.craftedsignal.io/tags/boot-configuration/","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cves":[],"_cs_exploited":false,"_cs_products":["Microsoft Defender XDR","SentinelOne Cloud Funnel","Elastic Defend"],"_cs_severities":["medium"],"_cs_tags":["boot-configuration","bcdedit","impact","windows"],"_cs_type":"advisory","_cs_vendors":["Microsoft","Crowdstrike","SentinelOne","Elastic"],"content_html":"\u003cp\u003eThis detection rule identifies the execution of \u003ccode\u003ebcdedit.exe\u003c/code\u003e with specific arguments that modify the boot configuration data (BCD) store in Windows systems. Attackers or malware may use this technique to disable Windows Error Recovery (\u003ccode\u003erecoveryenabled\u003c/code\u003e) or to ignore errors during the boot process (\u003ccode\u003ebootstatuspolicy ignoreallfailures\u003c/code\u003e). These modifications are often performed to prevent systems from recovering properly after an attack, particularly in ransomware scenarios. The rule is designed to work with data from Elastic Defend, CrowdStrike, Microsoft Defender XDR, SentinelOne Cloud Funnel, and Sysmon. The detection logic focuses on process execution events that include the relevant \u003ccode\u003ebcdedit.exe\u003c/code\u003e command-line arguments. Defenders should be aware of legitimate uses of \u003ccode\u003ebcdedit.exe\u003c/code\u003e by administrators for troubleshooting or data recovery purposes, so context is crucial.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eInitial Access: The attacker gains initial access to the system through various means, such as phishing or exploiting a vulnerability.\u003c/li\u003e\n\u003cli\u003ePrivilege Escalation: The attacker escalates privileges to gain administrative access, required to modify boot configuration settings.\u003c/li\u003e\n\u003cli\u003eReconnaissance: The attacker performs reconnaissance to identify the system\u0026rsquo;s configuration and identify appropriate targets for modification.\u003c/li\u003e\n\u003cli\u003eDisable Recovery: The attacker uses \u003ccode\u003ebcdedit.exe\u003c/code\u003e to disable Windows Error Recovery using the \u003ccode\u003e/set {default} recoveryenabled No\u003c/code\u003e command.\u003c/li\u003e\n\u003cli\u003eIgnore Boot Failures: The attacker uses \u003ccode\u003ebcdedit.exe\u003c/code\u003e to set the boot status policy to ignore all failures using the \u003ccode\u003e/set {default} bootstatuspolicy ignoreallfailures\u003c/code\u003e command.\u003c/li\u003e\n\u003cli\u003eSystem Impact: By modifying the boot configuration, the attacker inhibits system recovery, making it harder for the system to recover from errors or malicious activity.\u003c/li\u003e\n\u003cli\u003ePayload Execution: The attacker deploys and executes the primary malicious payload, such as ransomware, leveraging the modified boot configuration to maximize impact.\u003c/li\u003e\n\u003cli\u003eFinal Objective: The attacker achieves their final objective, which could include data encryption, data theft, or system disruption.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful modification of boot configuration data can lead to significant system instability and data loss. In ransomware attacks, this technique prevents the system from recovering, increasing the likelihood of the victim paying the ransom. While the exact number of affected organizations is unknown, this technique is widely used in ransomware campaigns and can affect any Windows system if successfully executed.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eDeploy the \u0026ldquo;Modification of Boot Configuration\u0026rdquo; Sigma rule to your SIEM and tune for your environment to detect the malicious use of \u003ccode\u003ebcdedit.exe\u003c/code\u003e described in this brief.\u003c/li\u003e\n\u003cli\u003eEnable Sysmon process creation logging to capture \u003ccode\u003ebcdedit.exe\u003c/code\u003e executions and their command-line arguments (Sysmon Event ID 1).\u003c/li\u003e\n\u003cli\u003eInvestigate any detected instances of \u003ccode\u003ebcdedit.exe\u003c/code\u003e modifying boot configuration settings to determine legitimacy, as described in the rule\u0026rsquo;s \u0026ldquo;Triage and analysis\u0026rdquo; section.\u003c/li\u003e\n\u003cli\u003eMonitor process execution logs for unexpected processes running \u003ccode\u003ebcdedit.exe\u003c/code\u003e with arguments related to disabling recovery or ignoring boot failures.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2024-01-03T15:30:00Z","date_published":"2024-01-03T15:30:00Z","id":"/briefs/2024-01-bcdedit-boot-config-modification/","summary":"This rule identifies the use of bcdedit.exe to modify boot configuration data, which may be indicative of a destructive attack or ransomware activity aimed at inhibiting system recovery by disabling error recovery or ignoring boot failures.","title":"Detection of Bcdedit Boot Configuration Modification","url":"https://feed.craftedsignal.io/briefs/2024-01-bcdedit-boot-config-modification/"}],"language":"en","title":"CraftedSignal Threat Feed — Boot-Configuration","version":"https://jsonfeed.org/version/1.1"}