CVE-2026-124739

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{"acknowledgement": "Red Hat would like to thank ducanhluu for reporting this issue.", "bugzilla": {"description": "busybox: httpd stack buffer overflow via an \"I:\" rule in a subdirectory httpd.conf", "id": "2571613", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2571613"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.5", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-787", "details": ["A flaw was found in BusyBox. When the httpd web server processes subdirectory configuration files, an overly long index page name can trigger a stack-based buffer overflow. An attacker with permissions to write to a subdirectory configuration file could exploit this vulnerability to execute arbitrary code with elevated privileges or cause a denial of service (DoS) by crashing the server process."], "mitigation": {"lang": "en:us", "value": "Prevent untrusted users from creating or modifying configuration files by restricting write permissions on all web root and subdirectory paths served by BusyBox httpd to administrative accounts only:\nchmod -R o-w /path/to/webroot\nAdditionally, ensure the BusyBox httpd process drops elevated privileges by specifying an unprivileged user with the `-u` flag upon execution:\nbusybox httpd -u nobody\nRestarting the daemon is required for process-level flag changes to take effect, which will temporarily terminate active network connections.\nCaveats: Running under a non-privileged user account prevents binding directly to privileged ports (below 1024) without additional system capabilities or port forwarding, and restricting directory permissions may interfere with workflows that require unprivileged file uploads."}, "name": "CVE-2026-124739", "package_state": [{"cpe": "cpe:/o:redhat:rhel_els:6", "fix_state": "Affected", "package_name": "busybox", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "busybox", "product_name": "Red Hat Hardened Images"}], "public_date": "2026-11-11T09:15:15Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-124739\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-124739"], "statement": "This vulnerability is rated as Important because successful exploitation allows a local user with write access to web-accessible directories to execute arbitrary code with elevated root privileges or trigger a denial of service. Within Red Hat environments, BusyBox is not deployed as a standard web server by default, significantly limiting exposure in standard installations. Exploitation specifically requires the BusyBox httpd service to be actively running and serving content from directories where untrusted users possess write permissions to introduce or modify local configuration files.", "threat_severity": "Important"}

{"created": "2026-11-11T23:15:09.530671+00:00", "updated": "2026-11-13T13:00:08.387378+00:00", "vendors": []}