{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","feed_url":"https://feed.craftedsignal.io/products/busybox-v1.38.0/feed.json","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cpes":["cpe:2.3:a:busybox:busybox:1.38.0:*:*:*:*:*:*:*"],"_cs_cves":[{"cvss":5.1,"id":"CVE-2026-38754"},{"cvss":2.9,"id":"CVE-2026-38755"},{"cvss":4.9,"id":"CVE-2026-38753"}],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":["Busybox v1.38.0"],"_cs_severities":["high"],"_cs_tags":["vulnerability","denial-of-service","heap-overflow","linux"],"_cs_type":"advisory","_cs_vendors":["Busybox"],"content_html":"\u003cp\u003eA critical heap overflow vulnerability, tracked as CVE-2026-38754, has been identified in Busybox version 1.38.0. The flaw resides within the \u003ccode\u003eifsbreakup()\u003c/code\u003e function, located in the \u003ccode\u003eshell/ash.c\u003c/code\u003e component of the utility. Attackers can exploit this vulnerability by supplying a specially crafted input, which leads to memory corruption in the heap. This ultimately results in a Denial of Service (DoS) condition, causing the Busybox application to crash or become unstable. Given Busybox's widespread use in embedded systems, IoT devices, and various Linux environments, successful exploitation could lead to significant operational disruptions for affected systems that rely on Busybox for core command-line functionalities. The vulnerability was published by Microsoft Security Response Center (MSRC).\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAn attacker identifies a target system utilizing Busybox version 1.38.0.\u003c/li\u003e\n\u003cli\u003eThe attacker crafts a malicious input string designed to exploit the heap overflow in the \u003ccode\u003eifsbreakup()\u003c/code\u003e function of the Busybox shell (ash.c). This input likely consists of specially formatted shell commands or arguments.\u003c/li\u003e\n\u003cli\u003eThe crafted input is delivered to the vulnerable Busybox instance. This could occur via a network service that processes shell commands, through local execution if the attacker has user access, or via other input vectors that feed into the Busybox shell.\u003c/li\u003e\n\u003cli\u003eThe Busybox shell attempts to parse and process the received malicious input.\u003c/li\u003e\n\u003cli\u003eDuring the parsing operation, the \u003ccode\u003eifsbreakup()\u003c/code\u003e function, which is responsible for tokenizing input strings, encounters the malformed data.\u003c/li\u003e\n\u003cli\u003eThe malformed input triggers a heap overflow within \u003ccode\u003eifsbreakup()\u003c/code\u003e, leading to memory corruption.\u003c/li\u003e\n\u003cli\u003eThe Busybox process subsequently crashes or becomes unresponsive due to the integrity of its memory being compromised.\u003c/li\u003e\n\u003cli\u003eThe target system experiences a Denial of Service as critical Busybox functionalities become unavailable, impacting system stability and operational capabilities.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eA successful exploitation of CVE-2026-38754 leads directly to a Denial of Service (DoS) condition on the affected Busybox instance. This can manifest as application crashes, system instability, or complete unavailability of services that rely on Busybox for shell command execution. Since Busybox is frequently used in resource-constrained environments such as embedded systems, IoT devices, and network equipment, a DoS could render critical infrastructure inoperable, disrupt communication, or make remote management impossible. While the immediate impact is DoS, persistent or repeated attacks could severely impede business operations for organizations utilizing vulnerable Busybox versions.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003ePrioritize patching Busybox installations to a version not affected by CVE-2026-38754 immediately upon availability.\u003c/li\u003e\n\u003cli\u003eMonitor system logs for unexpected Busybox process crashes or reboots, which could indicate a successful Denial of Service attack.\u003c/li\u003e\n\u003cli\u003eReview applications and services that interact with Busybox to ensure they employ robust input validation mechanisms to prevent the delivery of crafted input.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-07-21T07:29:28Z","date_published":"2026-07-21T07:19:06Z","id":"https://feed.craftedsignal.io/briefs/2026-07-busybox-heap-overflow-dos/","summary":"A heap overflow vulnerability (CVE-2026-38754) exists in the ifsbreakup() function (shell/ash.c) of Busybox v1.38.0. This flaw allows attackers to trigger a Denial of Service (DoS) by providing a specially crafted input, leading to application instability or unavailability.","title":"CVE-2026-38754: Busybox Heap Overflow Leads to Denial of Service","url":"https://feed.craftedsignal.io/briefs/2026-07-busybox-heap-overflow-dos/"}],"language":"en","title":"CraftedSignal Threat Feed - Busybox V1.38.0","version":"https://jsonfeed.org/version/1.1"}