{"id":"CVE-2026-120596","aliases":["EUVD-2026-115333","GHSA-mg75-66wv-hfxw"],"status":"published","title":"CVE-2026-120596","description":"A remotely exploitable denial-of-service vulnerability exists in the TCP options parser of the Nut/Net TCP/IP stack included in Nut/OS, developed by Ethernut/Egnite. Nut/OS releases up to version 5.1 are affected. An unauthenticated attacker can send a single TCP segment containing an unknown TCP option with a length byte of zero to any open TCP port on a vulnerable device. When processed, this malformed option triggers an infinite loop in the function NutTcpInputOptions, permanently blocking the TCP processing thread and rendering all TCP-based services unresponsive until the device is rebooted.","severity":{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"adp","from":"cve"},"epss":{"day":"2026-11-12","score":0.00375,"percentile":0.31968,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-835"],"published":"2026-11-02T17:04:18Z","modified":"2026-11-02T19:35:33Z","products":[{"vendor":"ethernut / egnite gmbh","product":"nut/net tcp/ip stack"}],"references":[{"url":"https://www.ethernut.de/en/download/index.html"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-120596"},{"url":"https://github.com/advisories/GHSA-mg75-66wv-hfxw"}],"sources":{"cve":[{"id":"CVE-2026-120596","title":"CVE-2026-120596","description":"A remotely exploitable denial-of-service vulnerability exists in the TCP options parser of the Nut/Net TCP/IP stack included in Nut/OS, developed by Ethernut/Egnite. Nut/OS releases up to version 5.1 are affected. An unauthenticated attacker can send a single TCP segment containing an unknown TCP option with a length byte of zero to any open TCP port on a vulnerable device. When processed, this malformed option triggers an infinite loop in the function NutTcpInputOptions, permanently blocking the TCP processing thread and rendering all TCP-based services unresponsive until the device is rebooted.","status":"published","published":"2026-11-02T17:04:18.611Z","modified":"2026-11-02T17:17:35.066Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"adp"}],"cwes":["CWE-835"],"updated_at":"2026-11-02T19:02:29.283836Z"}],"euvd":[{"id":"EUVD-2026-115333","description":"A remotely exploitable denial-of-service vulnerability exists in the TCP options parser of the Nut/Net TCP/IP stack included in Nut/OS, developed by Ethernut/Egnite. Nut/OS releases up to version 5.1 are affected. An unauthenticated attacker can send a single TCP segment containing an unknown TCP option with a length byte of zero to any open TCP port on a vulnerable device. When processed, this malformed option triggers an infinite loop in the function NutTcpInputOptions, permanently blocking the TCP processing thread and rendering all TCP-based services unresponsive until the device is rebooted.","status":"published","published":"2026-11-02T17:04:18Z","modified":"2026-11-02T17:17:35Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-03T05:08:39.764975Z"}],"ghsa":[{"id":"GHSA-mg75-66wv-hfxw","title":"A remotely exploitable denial-of-service vulnerability exists in the TCP options parser of the...","description":"A remotely exploitable denial-of-service vulnerability exists in the TCP options parser of the Nut/Net TCP/IP stack included in Nut/OS, developed by Ethernut/Egnite. Nut/OS releases up to version 5.1 are affected. An unauthenticated attacker can send a single TCP segment containing an unknown TCP option with a length byte of zero to any open TCP port on a vulnerable device. When processed, this malformed option triggers an infinite loop in the function NutTcpInputOptions, permanently blocking the TCP processing thread and rendering all TCP-based services unresponsive until the device is rebooted.","status":"published","published":"2026-11-02T18:32:28Z","modified":"2026-11-02T18:32:36Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"cwes":["CWE-835"],"updated_at":"2026-11-02T19:02:40.409728Z"}],"nvd":[{"id":"CVE-2026-120596","description":"A remotely exploitable denial-of-service vulnerability exists in the TCP options parser of the Nut/Net TCP/IP stack included in Nut/OS, developed by Ethernut/Egnite. Nut/OS releases up to version 5.1 are affected. An unauthenticated attacker can send a single TCP segment containing an unknown TCP option with a length byte of zero to any open TCP port on a vulnerable device. When processed, this malformed option triggers an infinite loop in the function NutTcpInputOptions, permanently blocking the TCP processing thread and rendering all TCP-based services unresponsive until the device is rebooted.","status":"published","published":"2026-11-02T17:17:40.003Z","modified":"2026-11-02T19:35:33.347Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-835"],"updated_at":"2026-11-03T00:02:42.67885Z"}]}}