{"id":"CVE-2026-2966","aliases":["DEBIAN-CVE-2026-2966","EUVD-2026-7602","GHSA-m5mm-h952-fxjj","JLSEC-2026-366","UBUNTU-CVE-2026-2966"],"status":"published","title":"Cesanta Mongoose DNS Transaction ID dns.c mg_sendnsreq random values","description":"A weakness has been identified in Cesanta Mongoose up to 7.20. The impacted element is the function mg_sendnsreq of the file /src/dns.c of the component DNS Transaction ID Handler. Executing a manipulation of the argument random can lead to insufficiently random values. The attack can be launched remotely. The attack requires a high level of complexity. The exploitability is regarded as difficult. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.","severity":{"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:N/SC:N/SI:N/SA:N/E:P","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00441,"percentile":0.38636,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-310","CWE-330"],"published":"2026-02-23T02:02:08Z","modified":"2026-10-28T02:30:49Z","fixes":[{"ecosystem":"Debian:14","package":"swupdate","fixed_in":["2025.12+dfsg-10"],"sources":["osv"]},{"ecosystem":"Julia","package":"Mongoose_jll","fixed_in":["7.21.0+0"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Debian:12","package":"swupdate","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2022.12+dfsg-4","2022.12+dfsg-4+deb12u1","2022.12+dfsg-4+deb12u1~bpo11+1","2022.12+dfsg-4+deb12u2","2023.05+dfsg-1","2023.05+dfsg-2","2023.05+dfsg-2~bpo12+1","2023.05+dfsg-3","2023.05+dfsg-4","2023.05+dfsg-5","2023.05+dfsg-5~bpo12+1","2023.12+dfsg-1","2023.12+dfsg-1~bpo12+1","2023.12.1+dfsg-1","2023.12.1+dfsg-1~bpo12+1","2023.12.1+dfsg-2","2023.12.1+dfsg-2~bpo12+1","2024.05+dfsg-1","2024.05.2+dfsg-1","2024.05.2+dfsg-2","2024.05.2+dfsg-2~bpo12+1","2024.12+dfsg-1","2024.12+dfsg-2","2024.12+dfsg-2~bpo12+1","2024.12.1+dfsg-1","2024.12.1+dfsg-1~bpo12+1","2024.12.1+dfsg-2","2024.12.1+dfsg-3","2024.12.1+dfsg-3~bpo12+1","2025.05+dfsg-1","2025.05+dfsg-2","2025.05+dfsg-2~bpo13+1","2025.05+dfsg-3","2025.05+dfsg-3~bpo13+1","2025.12+dfsg-1","2025.12+dfsg-10","2025.12+dfsg-10~bpo13+1","2025.12+dfsg-10~bpo13+2","2025.12+dfsg-2","2025.12+dfsg-2~bpo13+1","2025.12+dfsg-3","2025.12+dfsg-4","2025.12+dfsg-5","2025.12+dfsg-6","2025.12+dfsg-7","2025.12+dfsg-7~bpo13+1","2025.12+dfsg-8","2025.12+dfsg-9","2026.05+dfsg-1","2026.05+dfsg-2","2026.05+dfsg-3","2026.05+dfsg-3~bpo13+1","2026.05+dfsg-4","2026.05.1+dfsg-1","2026.05.1+dfsg-1~bpo13+1"]},{"source":"osv","ecosystem":"Debian:13","package":"swupdate","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2024.12.1+dfsg-3","2024.12.1+dfsg-3+deb13u1","2024.12.1+dfsg-3+deb13u2","2025.05+dfsg-1","2025.05+dfsg-2","2025.05+dfsg-2~bpo13+1","2025.05+dfsg-3","2025.05+dfsg-3~bpo13+1","2025.12+dfsg-1","2025.12+dfsg-10","2025.12+dfsg-10~bpo13+1","2025.12+dfsg-10~bpo13+2","2025.12+dfsg-2","2025.12+dfsg-2~bpo13+1","2025.12+dfsg-3","2025.12+dfsg-4","2025.12+dfsg-5","2025.12+dfsg-6","2025.12+dfsg-7","2025.12+dfsg-7~bpo13+1","2025.12+dfsg-8","2025.12+dfsg-9","2026.05+dfsg-1","2026.05+dfsg-2","2026.05+dfsg-3","2026.05+dfsg-3~bpo13+1","2026.05+dfsg-4","2026.05.1+dfsg-1","2026.05.1+dfsg-1~bpo13+1"]},{"source":"osv","ecosystem":"Debian:14","package":"swupdate","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2025.12+dfsg-10"}]}],"versions":["2024.12.1+dfsg-3","2025.05+dfsg-1","2025.05+dfsg-2","2025.05+dfsg-2~bpo13+1","2025.05+dfsg-3","2025.05+dfsg-3~bpo13+1","2025.12+dfsg-1","2025.12+dfsg-10~bpo13+1","2025.12+dfsg-10~bpo13+2","2025.12+dfsg-2","2025.12+dfsg-2~bpo13+1","2025.12+dfsg-3","2025.12+dfsg-4","2025.12+dfsg-5","2025.12+dfsg-6","2025.12+dfsg-7","2025.12+dfsg-7~bpo13+1","2025.12+dfsg-8","2025.12+dfsg-9"]},{"source":"osv","ecosystem":"Julia","package":"Mongoose_jll","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"7.21.0+0"}]}]},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"opencpn","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.0.0+dfsg-1"]},{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"opencpn","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.2.4+dfsg-1","5.6.0+dfsg1-1"]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"opencpn","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.8.4+dfsg-1","5.8.4+dfsg-1build3","5.8.4+dfsg-1build4"]},{"source":"osv","ecosystem":"Ubuntu:25.10","package":"opencpn","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1:5.10.2+dfsg-1"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"opencpn","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1:5.12.4+dfsg-1","1:5.14.1+dfsg-3","1:5.14.1+dfsg-4"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"opencpn","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1:5.10.2+dfsg-1","1:5.12.4+dfsg-1"]}],"products":[{"vendor":"automattic","product":"mongoose"},{"vendor":"cesanta","product":"mongoose"}],"references":[{"url":"https://vuldb.com/?id.347333","tags":["vdb-entry","technical-description","Third Party Advisory","VDB Entry","advisory","web","report"]},{"url":"https://vuldb.com/?ctiid.347333","tags":["signature","permissions-required","Permissions Required","VDB Entry","report","web"]},{"url":"https://vuldb.com/?submit.755304","tags":["third-party-advisory","Third Party Advisory","VDB Entry","advisory","web","report"]},{"url":"https://github.com/dwBruijn/CVEs/blob/main/Mongoose/mg_sendnsreq.md","tags":["related","Exploit","Third Party Advisory","web","report"]},{"url":"https://github.com/dwBruijn/CVEs/blob/main/Mongoose/mg_sendnsreq.md#poc","tags":["exploit","Exploit","Third Party Advisory","evidence","web","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-2966","tags":["advisory","web"]},{"url":"https://github.com/advisories/GHSA-m5mm-h952-fxjj","tags":["web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/2xxx/CVE-2026-2966.json","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-2966","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-2966","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-2966","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-2966","title":"Cesanta Mongoose DNS Transaction ID dns.c mg_sendnsreq random values","description":"A weakness has been identified in Cesanta Mongoose up to 7.20. The impacted element is the function mg_sendnsreq of the file /src/dns.c of the component DNS Transaction ID Handler. Executing a manipulation of the argument random can lead to insufficiently random values. The attack can be launched remotely. The attack requires a high level of complexity. The exploitability is regarded as difficult. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.","status":"published","published":"2026-02-23T02:02:08.202Z","modified":"2026-02-23T13:36:51.905Z","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:N/SC:N/SI:N/SA:N/E:P","level":"medium","assessor":"cna"},{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N/E:P/RL:X/RC:R","level":"low","assessor":"cna"},{"version":"3.0","score":3.7,"vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N/E:P/RL:X/RC:R","level":"low","assessor":"cna"},{"version":"2.0","score":2.6,"vector":"AV:N/AC:H/Au:N/C:N/I:P/A:N/E:POC/RL:ND/RC:UR","assessor":"cna"}],"cwes":["CWE-330","CWE-310"],"updated_at":"2026-11-02T13:48:46.911326Z"}],"euvd":[{"id":"EUVD-2026-7602","description":"A weakness has been identified in Cesanta Mongoose up to 7.20. The impacted element is the function mg_sendnsreq of the file /src/dns.c of the component DNS Transaction ID Handler. Executing a manipulation of the argument random can lead to insufficiently random values. The attack can be launched remotely. The attack requires a high level of complexity. The exploitability is regarded as difficult. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.","status":"published","published":"2026-02-23T02:02:08Z","modified":"2026-02-23T13:36:51Z","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:N/SC:N/SI:N/SA:N/E:P","level":"medium"}],"updated_at":"2026-11-02T19:48:32.640352Z"}],"ghsa":[{"id":"GHSA-m5mm-h952-fxjj","title":"A weakness has been identified in Cesanta Mongoose up to 7.20. The impacted element is the...","description":"A weakness has been identified in Cesanta Mongoose up to 7.20. The impacted element is the function mg_sendnsreq of the file /src/dns.c of the component DNS Transaction ID Handler. Executing a manipulation of the argument random can lead to insufficiently random values. The attack can be launched remotely. The attack requires a high level of complexity. The exploitability is regarded as difficult. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.","status":"published","published":"2026-02-23T03:30:22Z","modified":"2026-02-23T03:30:22Z","cvss":[{"version":"4.0","score":2.9,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/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":"low"},{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"low"}],"updated_at":"2026-11-02T15:06:19.172449Z"}],"nvd":[{"id":"CVE-2026-2966","description":"A weakness has been identified in Cesanta Mongoose up to 7.20. The impacted element is the function mg_sendnsreq of the file /src/dns.c of the component DNS Transaction ID Handler. Executing a manipulation of the argument random can lead to insufficiently random values. The attack can be launched remotely. The attack requires a high level of complexity. The exploitability is regarded as difficult. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.","status":"published","published":"2026-02-23T03:15:59.373Z","modified":"2026-06-17T10:32:07.993Z","cvss":[{"version":"4.0","score":2.9,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/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":"low","assessor":"secondary"},{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"low","assessor":"secondary"},{"version":"2.0","score":2.6,"vector":"AV:N/AC:H/Au:N/C:N/I:P/A:N","level":"low","assessor":"secondary"}],"cwes":["CWE-310","CWE-330"],"updated_at":"2026-11-02T14:12:06.63895Z"}],"osv":[{"id":"CVE-2026-2966","title":"Cesanta Mongoose DNS Transaction ID dns.c mg_sendnsreq random values","description":"A weakness has been identified in Cesanta Mongoose up to 7.20. The impacted element is the function mg_sendnsreq of the file /src/dns.c of the component DNS Transaction ID Handler. Executing a manipulation of the argument random can lead to insufficiently random values. The attack can be launched remotely. The attack requires a high level of complexity. The exploitability is regarded as difficult. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.","status":"published","published":"2026-02-23T02:02:08.202Z","modified":"2026-10-28T02:30:49.245905131Z","cvss":[{"version":"4.0","score":2.9,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P","level":"low"}],"cwes":["CWE-310","CWE-330"],"updated_at":"2026-11-02T15:45:00.530889Z"},{"id":"DEBIAN-CVE-2026-2966","description":"A weakness has been identified in Cesanta Mongoose up to 7.20. The impacted element is the function mg_sendnsreq of the file /src/dns.c of the component DNS Transaction ID Handler. Executing a manipulation of the argument random can lead to insufficiently random values. The attack can be launched remotely. The attack requires a high level of complexity. The exploitability is regarded as difficult. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.","status":"published","published":"2026-02-23T03:15:59.373Z","modified":"2026-10-01T03:03:02.808474984Z","cvss":[{"version":"4.0","score":2.9,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/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":"low"}],"updated_at":"2026-11-02T15:45:53.877573Z"},{"id":"JLSEC-2026-366","title":"A weakness has been identified in Cesanta Mongoose up to 7.20","description":"A weakness has been identified in Cesanta Mongoose up to 7.20. The impacted element is the function `mg_sendnsreq` of the file `/src/dns.c` of the component DNS Transaction ID Handler. Executing a manipulation of the argument random can lead to insufficiently random values. The attack can be launched remotely. The attack requires a high level of complexity. The exploitability is regarded as difficult. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.","status":"published","published":"2026-04-30T19:30:31.295Z","modified":"2026-07-25T18:24:22.252672415Z","cvss":[{"version":"2.0","score":2.6,"vector":"AV:N/AC:H/Au:N/C:N/I:P/A:N","level":"low"},{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"low"},{"version":"4.0","score":2.9,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/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":"low"}],"updated_at":"2026-11-02T15:47:18.573531Z"},{"id":"UBUNTU-CVE-2026-2966","description":"A weakness has been identified in Cesanta Mongoose up to 7.20. The impacted element is the function mg_sendnsreq of the file /src/dns.c of the component DNS Transaction ID Handler. Executing a manipulation of the argument random can lead to insufficiently random values. The attack can be launched remotely. The attack requires a high level of complexity. The exploitability is regarded as difficult. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.","status":"published","published":"2026-02-23T03:15:00Z","modified":"2026-10-17T12:59:57.834838065Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"low"},{"version":"4.0","score":2.9,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P","level":"low"}],"updated_at":"2026-11-02T16:56:11.640778Z"}]}}