{"id":"CVE-2026-102719","aliases":["EUVD-2026-89182","GHSA-3fp7-fjmc-gqr7","GHSA-j6gx-3j6v-3hm4"],"status":"published","title":"NetX Secure DTLS server issues predictable HelloVerifyRequest cookies, so a spoofed client can pass the return-routability check","description":"In Eclipse ThreadX NetX Duo versions 6.0 through 6.5.2.202603a, the NetX Secure DTLS server fills HelloVerifyRequest cookies from NX_RAND(), by default the C library rand(), with no key and no binding to the client. An attacker who can predict the generator's output can pass the cookie exchange from a spoofed address and make the server send its handshake flight to a victim, using it as a traffic reflector.","severity":{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:L","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00207,"percentile":0.10951,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-330","CWE-338"],"published":"2026-09-29T17:45:21Z","modified":"2026-11-04T09:36:15Z","products":[{"vendor":"eclipse foundation","product":"eclipse threadx netx duo"}],"references":[{"url":"https://github.com/eclipse-threadx/netxduo/security/advisories/GHSA-j6gx-3j6v-3hm4","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-102719","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-3fp7-fjmc-gqr7"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/102xxx/CVE-2026-102719.json","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-102719","title":"NetX Secure DTLS server issues predictable HelloVerifyRequest cookies, so a spoofed client can pass the return-routability check","description":"In Eclipse ThreadX NetX Duo versions 6.0 through 6.5.2.202603a, the NetX Secure DTLS server fills HelloVerifyRequest cookies from NX_RAND(), by default the C library rand(), with no key and no binding to the client. An attacker who can predict the generator's output can pass the cookie exchange from a spoofed address and make the server send its handshake flight to a victim, using it as a traffic reflector.","status":"published","published":"2026-09-29T17:45:21.609Z","modified":"2026-11-04T09:36:15.185Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:L","level":"medium","assessor":"cna"}],"cwes":["CWE-338"],"updated_at":"2026-11-04T10:28:06.820135Z"}],"euvd":[{"id":"EUVD-2026-89182","description":"In Eclipse ThreadX NetX Duo versions 6.0 through 6.5.2.202603a, the NetX Secure DTLS server fills HelloVerifyRequest cookies from NX_RAND(), by default the C library rand(), with no key and no binding to the client. An attacker who can predict the generator's output can pass the cookie exchange from a spoofed address and make the server send its handshake flight to a victim, using it as a traffic reflector.","status":"published","published":"2026-09-29T17:45:21Z","modified":"2026-11-04T09:36:15Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:L","level":"medium"}],"updated_at":"2026-11-04T11:02:20.706611Z"}],"ghsa":[{"id":"GHSA-3fp7-fjmc-gqr7","title":"Predictable DTLS HelloVerifyRequest Cookie in NetX Secure","description":"Predictable DTLS HelloVerifyRequest Cookie in NetX Secure","status":"published","published":"2026-09-29T18:32:01Z","modified":"2026-11-04T12:31:30Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium"}],"cwes":["CWE-330","CWE-338"],"updated_at":"2026-11-04T12:34:56.311878Z"}],"nvd":[{"id":"CVE-2026-102719","description":"In Eclipse ThreadX NetX Duo versions 6.0 through 6.5.2.202603a, the NetX Secure DTLS server fills HelloVerifyRequest cookies from NX_RAND(), by default the C library rand(), with no key and no binding to the client. An attacker who can predict the generator's output can pass the cookie exchange from a spoofed address and make the server send its handshake flight to a victim, using it as a traffic reflector.","status":"published","published":"2026-09-29T18:17:11.24Z","modified":"2026-11-04T10:17:23.56Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium","assessor":"secondary"}],"cwes":["CWE-338"],"updated_at":"2026-11-04T11:59:36.745762Z"}],"osv":[{"id":"CVE-2026-102719","title":"NetX Secure DTLS server issues predictable HelloVerifyRequest cookies, so a spoofed client can pass the return-routability check","description":"In Eclipse ThreadX NetX Duo versions 6.0 through 6.5.2.202603a, the NetX Secure DTLS server fills HelloVerifyRequest cookies from NX_RAND(), by default the C library rand(), with no key and no binding to the client. An attacker who can predict the generator's output can pass the cookie exchange from a spoofed address and make the server send its handshake flight to a victim, using it as a traffic reflector.","status":"published","published":"2026-09-29T17:45:21.609Z","modified":"2026-11-07T10:46:59.408559382Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:L","level":"medium"}],"cwes":["CWE-338"],"updated_at":"2026-11-07T11:15:38.581573Z"}]}}