{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","feed_url":"https://feed.craftedsignal.io/tags/cve-2026-44673/feed.json","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cpes":[],"_cs_cves":[{"cvss":7.5,"id":"CVE-2026-44673"}],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":[],"_cs_severities":["high"],"_cs_tags":["libyang","heap-buffer-overflow","integer-overflow","CVE-2026-44673"],"_cs_type":"advisory","_cs_vendors":["Microsoft"],"content_html":"\u003cp\u003eCVE-2026-44673 describes a vulnerability within the libyang library, specifically an integer overflow in the \u003ccode\u003elyb_read_string()\u003c/code\u003e function. The vulnerability occurs when handling string lengths during the parsing of LYB (yang binary) formatted data. An attacker could potentially exploit this flaw by crafting a malicious LYB file that triggers an integer overflow, leading to a heap buffer overflow during memory allocation and data processing. Successful exploitation could allow an attacker to execute arbitrary code within the context of the application using the vulnerable library. The vulnerability was published in May 2026.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAn attacker crafts a malicious LYB file containing a specially formatted string length field.\u003c/li\u003e\n\u003cli\u003eThe application using the vulnerable libyang library attempts to parse the LYB file.\u003c/li\u003e\n\u003cli\u003eThe \u003ccode\u003elyb_read_string()\u003c/code\u003e function is called to read the string from the LYB file.\u003c/li\u003e\n\u003cli\u003eThe function attempts to allocate memory on the heap based on the provided length.\u003c/li\u003e\n\u003cli\u003eDue to the crafted input, an integer overflow occurs during the length calculation.\u003c/li\u003e\n\u003cli\u003eThis results in a smaller-than-expected memory allocation.\u003c/li\u003e\n\u003cli\u003eThe \u003ccode\u003elyb_read_string()\u003c/code\u003e function proceeds to write the string data into the undersized buffer, causing a heap buffer overflow.\u003c/li\u003e\n\u003cli\u003eThe attacker leverages the heap buffer overflow to overwrite adjacent memory regions, potentially leading to arbitrary code execution.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation of CVE-2026-44673 can lead to arbitrary code execution within the context of the application utilizing the vulnerable libyang library. This could allow an attacker to gain control of the affected system, potentially leading to data theft, system compromise, or denial of service. The specific impact will depend on the privileges of the application and the attacker\u0026rsquo;s ability to craft a successful exploit.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eApply the security patch provided by Microsoft to address CVE-2026-44673 as soon as it becomes available.\u003c/li\u003e\n\u003cli\u003eDeploy the Sigma rule below to detect potential exploitation attempts based on process execution patterns after the vulnerability is triggered.\u003c/li\u003e\n\u003cli\u003eMonitor network traffic for suspicious LYB file uploads or transfers as a potential initial access vector.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-05-16T07:16:29Z","date_published":"2026-05-16T07:16:29Z","id":"https://feed.craftedsignal.io/briefs/2026-05-libyang-heap-overflow/","summary":"CVE-2026-44673 describes an integer overflow in the lyb_read_string() function of the libyang library that can lead to a heap buffer overflow, potentially allowing for arbitrary code execution.","title":"CVE-2026-44673 libyang Integer Overflow Leads to Heap Buffer Overflow","url":"https://feed.craftedsignal.io/briefs/2026-05-libyang-heap-overflow/"}],"language":"en","title":"CraftedSignal Threat Feed — CVE-2026-44673","version":"https://jsonfeed.org/version/1.1"}