{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata — refreshed continuously.","feed_url":"https://feed.craftedsignal.io/tags/input-validation/","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cves":[{"cvss":7.8,"id":"CVE-2026-26143"}],"_cs_exploited":false,"_cs_products":[],"_cs_severities":["high"],"_cs_tags":["cve-2026-26143","powershell","input-validation","bypass-uac","windows"],"_cs_type":"advisory","_cs_vendors":[],"content_html":"\u003cp\u003eCVE-2026-26143 describes a vulnerability in Microsoft PowerShell stemming from improper input validation. This flaw could allow a local, unauthorized attacker to bypass security features implemented within PowerShell. The vulnerability has a CVSS v3.1 score of 7.8, indicating a high severity. Successful exploitation could lead to significant compromise of the affected system. The vulnerability was reported to Microsoft and assigned CVE-2026-26143. Defenders should prioritize patching affected systems to mitigate the risk. The affected versions of PowerShell are not explicitly stated in the source material, therefore all installations of PowerShell on Windows should be considered potentially vulnerable.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAttacker gains local access to a Windows system. This could be through existing malware, physical access, or other initial access vectors.\u003c/li\u003e\n\u003cli\u003eAttacker crafts a malicious PowerShell command or script designed to exploit the input validation vulnerability (CVE-2026-26143).\u003c/li\u003e\n\u003cli\u003eThe attacker executes the malicious PowerShell command, bypassing intended security controls due to the input validation flaw.\u003c/li\u003e\n\u003cli\u003ePowerShell processes the crafted input, failing to properly sanitize or validate it.\u003c/li\u003e\n\u003cli\u003eThe bypassed security feature allows the attacker to perform actions that would normally be restricted, such as elevated privileges.\u003c/li\u003e\n\u003cli\u003eAttacker leverages the bypassed security feature to execute unauthorized code or modify system configurations.\u003c/li\u003e\n\u003cli\u003eThe attacker can now maintain persistence via registry keys (T1547.001) or scheduled tasks (T1053.005).\u003c/li\u003e\n\u003cli\u003eThe attacker achieves their objective, which could include data exfiltration, system compromise, or further lateral movement within the network.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation of CVE-2026-26143 can allow a local attacker to bypass security features within Microsoft PowerShell, potentially leading to arbitrary code execution with elevated privileges. This vulnerability could lead to a full system compromise. The number of potential victims is substantial, as PowerShell is a standard component of Windows operating systems. Systems lacking the security patch are vulnerable.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eApply the security update provided by Microsoft for CVE-2026-26143 to remediate the improper input validation vulnerability.\u003c/li\u003e\n\u003cli\u003eImplement the Sigma rule \u0026ldquo;Detect Suspicious PowerShell Input Validation Bypass\u0026rdquo; to identify potential exploitation attempts in your environment.\u003c/li\u003e\n\u003cli\u003eMonitor PowerShell execution logs for suspicious command-line arguments and script content, which could indicate an attempt to exploit this vulnerability.\u003c/li\u003e\n\u003cli\u003eRestrict local user access to reduce the attack surface and limit the potential for local exploitation.\u003c/li\u003e\n\u003cli\u003eEnable PowerShell logging and auditing to capture detailed information about PowerShell activity, which can aid in detecting and investigating suspicious behavior.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-04-15T12:00:00Z","date_published":"2026-04-15T12:00:00Z","id":"/briefs/2026-04-powershell-input-validation-bypass/","summary":"An improper input validation vulnerability (CVE-2026-26143) in Microsoft PowerShell allows an unauthorized local attacker to bypass security features.","title":"Microsoft PowerShell Improper Input Validation Vulnerability (CVE-2026-26143)","url":"https://feed.craftedsignal.io/briefs/2026-04-powershell-input-validation-bypass/"},{"_cs_actors":[],"_cs_cves":[{"cvss":8.4,"id":"CVE-2026-27306"}],"_cs_exploited":false,"_cs_products":[],"_cs_severities":["medium"],"_cs_tags":["cve-2026-27306","coldfusion","code execution","input validation"],"_cs_type":"advisory","_cs_vendors":[],"content_html":"\u003cp\u003eAdobe ColdFusion versions 2023.18, 2025.6, and earlier are susceptible to an improper input validation vulnerability identified as CVE-2026-27306. Successful exploitation of this vulnerability allows an attacker with elevated privileges to execute arbitrary code within the context of the current user. The attack necessitates user interaction, specifically the opening of a malicious file crafted by the attacker. This vulnerability poses a risk to organizations utilizing affected ColdFusion versions, as it could lead to compromised systems and data if exploited successfully. Defenders need to ensure that their systems are up to date to mitigate this risk.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eThe attacker identifies a vulnerable ColdFusion server running a version prior to 2023.18 or 2025.6.\u003c/li\u003e\n\u003cli\u003eThe attacker crafts a malicious file designed to exploit the improper input validation vulnerability (CVE-2026-27306). This file could be any format handled by ColdFusion that allows for input validation flaws, like a .cfm or .cfc file.\u003c/li\u003e\n\u003cli\u003eThe attacker social engineers a user with elevated privileges to download and open the malicious file.\u003c/li\u003e\n\u003cli\u003eWhen the user opens the file, ColdFusion processes it, triggering the input validation vulnerability.\u003c/li\u003e\n\u003cli\u003eThe improper input validation allows the attacker to inject arbitrary code into the ColdFusion process.\u003c/li\u003e\n\u003cli\u003eThe injected code executes within the context of the user who opened the file, granting the attacker the same privileges.\u003c/li\u003e\n\u003cli\u003eThe attacker can then use this access to install malware, steal sensitive data, or further compromise the system.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation of CVE-2026-27306 allows an attacker with elevated privileges to achieve arbitrary code execution. The attacker gains access to the system with the privileges of the user who opened the malicious file. This could lead to the compromise of sensitive data, the installation of backdoors, or the complete takeover of the ColdFusion server. While the number of victims and specific sectors targeted are not specified in the provided context, any organization using a vulnerable version of ColdFusion is at risk.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eApply the security patch provided by Adobe to address CVE-2026-27306 on all ColdFusion servers. Refer to the advisory link in the references section.\u003c/li\u003e\n\u003cli\u003eImplement user training to educate privileged users about the risks of opening files from untrusted sources to mitigate the user interaction requirement of the exploit.\u003c/li\u003e\n\u003cli\u003eEnable and review ColdFusion logs for suspicious activity related to file processing or code execution, which could indicate exploitation attempts.\u003c/li\u003e\n\u003cli\u003eDeploy the Sigma rules in this brief to your SIEM to detect exploitation attempts.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-04-15T12:00:00Z","date_published":"2026-04-15T12:00:00Z","id":"/briefs/2026-04-coldfusion-code-exec/","summary":"An improper input validation vulnerability in Adobe ColdFusion versions 2023.18, 2025.6, and earlier (CVE-2026-27306) could lead to arbitrary code execution if a privileged user opens a specially crafted malicious file.","title":"Adobe ColdFusion Improper Input Validation Vulnerability (CVE-2026-27306)","url":"https://feed.craftedsignal.io/briefs/2026-04-coldfusion-code-exec/"}],"language":"en","title":"CraftedSignal Threat Feed — Input-Validation","version":"https://jsonfeed.org/version/1.1"}