[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"$fx2x_6jYRv6OQKlwemAQ4fiynXwbsn4tGVueiZkg3eDk":3},{"article":4,"iocs":43,"watch_terms":47,"solutions":48,"lesson":140},{"id":5,"title":6,"slug":7,"summary":8,"ai_summary":9,"brief":10,"url":11,"image_url":12,"published_at":13,"ingested_at":14,"relevance_score":15,"entities":16,"category_id":25,"category":26,"article_tags":30},"8d53b644-70b4-471b-b7a5-db8fd0bdb472","New SignDrop Zero-Day Exploit Turns Windows CLFS Security Feature Into SYSTEM Access","new-signdrop-zero-day-exploit-turns-windows-clfs-security-feature-into-system-ac-c892fb","Public exploit code released earlier this week claims that a local Windows user can gain SYSTEM privileges through the Common Log File System driver. The proof of concept, called SignDrop, targets a log-authentication feature added to the driver last year. It abuses how clfs.sys creates companion files when a privileged process opens a prepared log, using path redirection to take control of","A new local privilege escalation exploit named SignDrop targets a log-authentication feature in Windows' Common Log File System (CLFS) driver. The exploit abuses how clfs.sys creates companion files, using path redirection to allow a standard user to create a SYSTEM-level file, which can be chained into a SYSTEM shell. While Microsoft has not confirmed the flaw or released a fix, independent testing confirmed the exploit works, though it may not be reliable enough for operational use and requires Defender to be enabled.","New SignDrop zero-day exploit allows local Windows users to gain SYSTEM privileges via CLFS driver.","https:\u002F\u002Fthehackernews.com\u002F2026\u002F11\u002Fnew-signdrop-zero-day-exploit-turns.html","https:\u002F\u002Fblogger.googleusercontent.com\u002Fimg\u002Fb\u002FR29vZ2xl\u002FAVvXsEh-9BW-gpid0fJ4GJSsWoqjYl5qF_EdYchTcxeNjFfMV-MCcvSRTs-rAmiHKNX3M2dr66bJcfUelNR5CR9g-JLKPkMrROsqrM6hf563hIMklj5v08uYDtEp7pdYPcs5Y5TEGxgTWTHDG_Q-L8Tbq12yo57xp0GOlYk8g05nU3peuA_kedIXtggnakiiCGM\u002Fs1600\u002Fsigndrop.jpg","2026-11-12T17:50:27+00:00","2026-11-12T19:00:27.337317+00:00",8,[17,20,23],{"name":18,"type":19},"Windows","product",{"name":21,"type":22},"CLFS","technology",{"name":24,"type":19},"Defender","80544778-fabb-4dcd-aa35-17492e5dcf4f",{"id":25,"icon":27,"name":28,"slug":29},null,"Vulnerabilities","vulnerabilities",[31,36,38],{"category":32},{"id":33,"icon":27,"name":34,"slug":35},"574f766a-fb3f-487c-8d2c-0720ae75471b","Zero-day","zero-day",{"category":37},{"id":25,"icon":27,"name":28,"slug":29},{"category":39},{"id":40,"icon":27,"name":41,"slug":42},"89f78b1c-3503-45a1-9fc7-e23d2ce1c6d5","Malware","malware",[44],{"type":42,"value":45,"context":46},"SignDrop","Name of the proof-of-concept exploit targeting the CLFS driver.",[18,24],{"controls":49,"vendors":136},[50,78,107],{"slug":51,"name":52,"problem":53,"products":54},"privileged-access-management","Privileged access management (PAM)","Admin accounts stop being one stolen password away from control of everything.",[55,63,71],{"vendor_slug":56,"vendor_name":57,"vendor_logo":58,"product_slug":59,"product_name":60,"url":61,"description":62},"palo-alto-networks","Palo Alto Networks","\u002Fvendor-logos\u002Fpalo-alto-networks.png","idira-privileged-access-management","Idira Privileged Access Management","https:\u002F\u002Fwww.paloaltonetworks.com\u002Fidira\u002Fhuman\u002Fprivileged-access-management","Privileged access management from the former CyberArk portfolio: vaulting, rotation, just-in-time access and session monitoring.",{"vendor_slug":64,"vendor_name":65,"vendor_logo":66,"product_slug":67,"product_name":68,"url":69,"description":70},"beyondtrust","BeyondTrust","\u002Fvendor-logos\u002Fbeyondtrust.png","password-safe","BeyondTrust Password Safe","https:\u002F\u002Fwww.beyondtrust.com\u002Fproducts\u002Fpassword-safe","Privileged password and session management.",{"vendor_slug":72,"vendor_name":73,"vendor_logo":74,"product_slug":51,"product_name":75,"url":76,"description":77},"threatlocker","ThreatLocker","\u002Fvendor-logos\u002Fthreatlocker.png","Privileged Access Management","https:\u002F\u002Fwww.threatlocker.com\u002Fcapabilities\u002Fprivileged-access-management","Gives elevated rights to specific applications only where needed, so users do not need local admin accounts.",{"slug":79,"name":80,"problem":81,"products":82},"patch-management","Automated patch management","Known holes get closed in days, not months.",[83,91,99],{"vendor_slug":84,"vendor_name":85,"vendor_logo":86,"product_slug":87,"product_name":88,"url":89,"description":90},"ninjaone","NinjaOne","\u002Fvendor-logos\u002Fninjaone.png","ninjaone-patch-management","NinjaOne Patch Management","https:\u002F\u002Fwww.ninjaone.com\u002Fpatch-management\u002F","Automated patching of operating systems and third-party applications from the cloud.",{"vendor_slug":92,"vendor_name":93,"vendor_logo":94,"product_slug":95,"product_name":96,"url":97,"description":98},"ivanti","Ivanti","\u002Fvendor-logos\u002Fivanti.png","neurons-patch-management","Ivanti Neurons for Patch Management","https:\u002F\u002Fwww.ivanti.com\u002Fproducts\u002Fivanti-neurons-for-patch-management","Risk-based patch management for operating systems and third-party applications.",{"vendor_slug":100,"vendor_name":101,"vendor_logo":102,"product_slug":103,"product_name":104,"url":105,"description":106},"microsoft","Microsoft","\u002Fvendor-logos\u002Fmicrosoft.png","intune","Microsoft Intune","https:\u002F\u002Fwww.microsoft.com\u002Fen-us\u002Fsecurity\u002Fbusiness\u002Fmicrosoft-intune","Device management for Windows, macOS, iOS and Android, including update rings and compliance policies.",{"slug":108,"name":109,"problem":110,"products":111},"endpoint-detection-response","Endpoint detection and response (EDR and XDR)","Malware and hands-on-keyboard attackers on laptops and servers get spotted and stopped.",[112,120,128],{"vendor_slug":113,"vendor_name":114,"vendor_logo":115,"product_slug":116,"product_name":117,"url":118,"description":119},"crowdstrike","CrowdStrike","\u002Fvendor-logos\u002Fcrowdstrike.png","falcon-insight-xdr","Falcon Insight XDR","https:\u002F\u002Fwww.crowdstrike.com\u002Fen-us\u002Fplatform\u002Fendpoint-security\u002Ffalcon-insight-xdr\u002F","Endpoint detection and response with extended detection across other security tools.",{"vendor_slug":121,"vendor_name":122,"vendor_logo":123,"product_slug":124,"product_name":125,"url":126,"description":127},"sophos","Sophos","\u002Fvendor-logos\u002Fsophos.png","sophos-endpoint","Sophos Endpoint","https:\u002F\u002Fwww.sophos.com\u002Fen-us\u002Fproducts\u002Fendpoint-security","Endpoint protection with Intercept X anti-ransomware technology and EDR.",{"vendor_slug":129,"vendor_name":130,"vendor_logo":131,"product_slug":132,"product_name":133,"url":134,"description":135},"elastic","Elastic","\u002Fvendor-logos\u002Felastic.png","elastic-security","Elastic Security","https:\u002F\u002Fwww.elastic.co\u002Fsecurity","SIEM and endpoint security built on Elasticsearch, with open detection rules.",[137],{"slug":100,"name":101,"logo_path":102,"roles":138},[139],"affected",{"slug":141,"title":142,"body":143,"framework_refs":144,"framework_notes":150},"windows-clfs-zero-day-enables-system-privilege-escalation-before-patch-exists","Windows CLFS Zero-Day Enables SYSTEM Privilege Escalation Before Patch Exists","The SignDrop exploit abuses a design flaw in Windows' Common Log File System (CLFS) driver, allowing a standard user to leverage path redirection during companion file creation to gain SYSTEM-level privileges. This is a zero-day, meaning no vendor patch currently exists, leaving organizations exposed with no straightforward remediation path. The vulnerability demonstrates how trusted OS components — particularly logging subsystems — can be weaponized to bypass security boundaries entirely. Organizations relying solely on vendor patching cycles are at significant risk during the gap between discovery and an official fix.",[145,146,147,148,149],"CIS Control 7: Continuous Vulnerability Management","CIS Control 10: Malware Defenses","NIST SP 800-53 SI-2: Flaw Remediation","MITRE ATT&CK T1068: Exploitation for Privilege Escalation","NIS2 Article 21(2)(e)",{"NIS2 Article 21(2)(e)":151,"CIS Control 10: Malware Defenses":152,"NIST SP 800-53 SI-2: Flaw Remediation":153,"CIS Control 7: Continuous Vulnerability Management":154,"MITRE ATT&CK T1068: Exploitation for Privilege Escalation":155},"This point requires entities to address vulnerability handling and disclosure in their security practices, which is critical here given the absence of a vendor patch and the need for proactive compensating controls.","The exploit chain's effectiveness is partially conditional on Defender's state, highlighting the importance of consistent, managed endpoint protection to detect or disrupt privilege escalation attempts.","SI-2 requires organizations to have processes for identifying and remediating flaws, including interim compensating controls when official patches do not yet exist, as is the case with this CLFS zero-day.","This control requires organizations to track and respond to vulnerabilities — including zero-days — through compensating controls when patches are unavailable, directly addressing the gap created by SignDrop having no current vendor fix.","SignDrop directly implements this technique by exploiting a vulnerability in the CLFS driver to escalate from a standard user to SYSTEM privileges on a Windows host."]