{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","feed_url":"https://feed.craftedsignal.io/tags/filename-sanitization/feed.json","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cpes":[],"_cs_cves":[{"cvss":7.1,"id":"CVE-2026-25789"}],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":[],"_cs_severities":["medium"],"_cs_tags":["xss","filename-sanitization","web-application"],"_cs_type":"advisory","_cs_vendors":["Siemens AG"],"content_html":"\u003cp\u003eCVE-2026-25789 exposes a vulnerability affecting certain devices where the Firmware Update page lacks proper filename validation and sanitization. A remote attacker could exploit this by crafting a malicious filename containing JavaScript code and socially engineering a user into selecting this \u0026ldquo;firmware\u0026rdquo; file for upload. The malicious JavaScript would then execute within the context of the authenticated user\u0026rsquo;s session, even without the file being fully uploaded, potentially allowing the attacker to hijack the user\u0026rsquo;s session or steal their credentials. This vulnerability highlights the importance of proper input validation to prevent cross-site scripting (XSS) attacks. Siemens AG has acknowledged this vulnerability.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAttacker identifies a vulnerable device with a Firmware Update page.\u003c/li\u003e\n\u003cli\u003eAttacker crafts a malicious filename containing embedded JavaScript code (e.g., \u003ccode\u003e\u0026lt;script\u0026gt;alert(\u0026quot;XSS\u0026quot;)\u0026lt;/script\u0026gt;.bin\u003c/code\u003e).\u003c/li\u003e\n\u003cli\u003eAttacker hosts or distributes the malicious \u0026ldquo;firmware\u0026rdquo; file.\u003c/li\u003e\n\u003cli\u003eAttacker uses social engineering to trick a user into selecting the malicious file on the Firmware Update page.\u003c/li\u003e\n\u003cli\u003eThe user selects the malicious file for upload through the web interface.\u003c/li\u003e\n\u003cli\u003eThe vulnerable device processes the filename without proper sanitization.\u003c/li\u003e\n\u003cli\u003eThe embedded JavaScript code is executed in the user\u0026rsquo;s browser session.\u003c/li\u003e\n\u003cli\u003eAttacker gains control of the user\u0026rsquo;s session, enabling credential theft or other malicious activities.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation of CVE-2026-25789 can lead to session hijacking and credential theft. An attacker could gain unauthorized access to the device\u0026rsquo;s management interface, potentially modifying device configurations, injecting malware, or accessing sensitive data. While the NVD entry does not specify the number of affected devices, it is classified as HIGH severity with a CVSS v3.1 score of 7.1.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eExamine web server logs for requests to the Firmware Update page containing suspicious filenames with JavaScript-related keywords using the Sigma rule \u0026ldquo;Detect Suspicious Firmware Update Filenames\u0026rdquo;.\u003c/li\u003e\n\u003cli\u003eImplement input validation and sanitization on the Firmware Update page to prevent the execution of arbitrary JavaScript code.\u003c/li\u003e\n\u003cli\u003eEducate users about the risks of downloading and uploading firmware files from untrusted sources.\u003c/li\u003e\n\u003cli\u003eApply the security patch provided by Siemens AG to remediate CVE-2026-25789 (reference: \u003ca href=\"https://cert-portal.siemens.com/productcert/html/ssa-688146.html)\"\u003ehttps://cert-portal.siemens.com/productcert/html/ssa-688146.html)\u003c/a\u003e.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-05-12T10:20:31Z","date_published":"2026-05-12T10:20:31Z","id":"https://feed.craftedsignal.io/briefs/2026-05-cve-2026-25789/","summary":"CVE-2026-25789 describes a vulnerability where affected devices do not properly validate and sanitize filenames on the Firmware Update page, potentially allowing a remote attacker to execute malicious JavaScript in the context of the user's session through social engineering, leading to session hijacking or credential theft.","title":"CVE-2026-25789 - Firmware Update Page Filename Sanitization Vulnerability","url":"https://feed.craftedsignal.io/briefs/2026-05-cve-2026-25789/"}],"language":"en","title":"CraftedSignal Threat Feed — Filename-Sanitization","version":"https://jsonfeed.org/version/1.1"}