{"id":"CVE-2026-2967","state":"PUBLISHED","title":"Cesanta Mongoose TCP Sequence Number net_builtin.c getpeer verification of source","description":"A security vulnerability has been detected in Cesanta Mongoose up to 7.20. This affects the function getpeer of the file /src/net_builtin.c of the component TCP Sequence Number Handler. The manipulation leads to improper verification of source of a communication channel. The attack may be initiated remotely. The attack's complexity is rated as high. The exploitability is reported as difficult. The exploit has been disclosed publicly and may be used. The vendor was contacted early about this disclosure but did not respond in any way.","publishedAt":"2026-02-23T02:32:07.568Z","updatedAt":"2026-02-23T13:32:57.830Z","severity":{"score":6.3,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P","source":"VulDB"},"assigner":"VulDB","products":["Cesanta Mongoose"],"affected":[{"vendor":"Cesanta","product":"Mongoose","versions":[{"version":"7.0","status":"affected"},{"version":"7.1","status":"affected"},{"version":"7.2","status":"affected"},{"version":"7.3","status":"affected"},{"version":"7.4","status":"affected"},{"version":"7.5","status":"affected"},{"version":"7.6","status":"affected"},{"version":"7.7","status":"affected"},{"version":"7.8","status":"affected"},{"version":"7.9","status":"affected"},{"version":"7.10","status":"affected"},{"version":"7.11","status":"affected"},{"version":"7.12","status":"affected"},{"version":"7.13","status":"affected"},{"version":"7.14","status":"affected"},{"version":"7.15","status":"affected"},{"version":"7.16","status":"affected"},{"version":"7.17","status":"affected"},{"version":"7.18","status":"affected"},{"version":"7.19","status":"affected"},{"version":"7.20","status":"affected"}],"cpes":["cpe:2.3:a:cesanta:mongoose:*:*:*:*:*:*:*:*"],"modules":["TCP Sequence Number Handler"]}],"references":["https://vuldb.com/?id.347334","https://vuldb.com/?ctiid.347334","https://vuldb.com/?submit.755450","https://github.com/dwBruijn/CVEs/blob/main/Mongoose/tcp_rst.md","https://github.com/dwBruijn/CVEs/blob/main/Mongoose/tcp_rst.md#poc"],"weaknesses":["CWE-940"],"ingestedAt":"2026-10-29T20:11:31.369Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/2xxx/CVE-2026-2967.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-2967","state":"PUBLISHED","datePublished":"2026-02-23T02:32:07.568Z","dateUpdated":"2026-02-23T13:32:57.830Z","assignerShortName":"VulDB","assignerOrgId":"1af790b2-7ee1-4545-860a-a788eba489b5","dateReserved":"2026-02-22T07:57:28.584Z"},"containers":{"cna":{"title":"Cesanta Mongoose TCP Sequence Number net_builtin.c getpeer verification of source","descriptions":[{"lang":"en","value":"A security vulnerability has been detected in Cesanta Mongoose up to 7.20. This affects the function getpeer of the file /src/net_builtin.c of the component TCP Sequence Number Handler. The manipulation leads to improper verification of source of a communication channel. The attack may be initiated remotely. The attack's complexity is rated as high. The exploitability is reported as difficult. The exploit has been disclosed publicly and may be used. The vendor was contacted early about this disclosure but did not respond in any way."}],"affected":[{"vendor":"Cesanta","product":"Mongoose","versions":[{"version":"7.0","status":"affected"},{"version":"7.1","status":"affected"},{"version":"7.2","status":"affected"},{"version":"7.3","status":"affected"},{"version":"7.4","status":"affected"},{"version":"7.5","status":"affected"},{"version":"7.6","status":"affected"},{"version":"7.7","status":"affected"},{"version":"7.8","status":"affected"},{"version":"7.9","status":"affected"},{"version":"7.10","status":"affected"},{"version":"7.11","status":"affected"},{"version":"7.12","status":"affected"},{"version":"7.13","status":"affected"},{"version":"7.14","status":"affected"},{"version":"7.15","status":"affected"},{"version":"7.16","status":"affected"},{"version":"7.17","status":"affected"},{"version":"7.18","status":"affected"},{"version":"7.19","status":"affected"},{"version":"7.20","status":"affected"}],"cpes":["cpe:2.3:a:cesanta:mongoose:*:*:*:*:*:*:*:*"],"modules":["TCP Sequence Number Handler"]}],"references":[{"url":"https://vuldb.com/?id.347334","name":"VDB-347334 | Cesanta Mongoose TCP Sequence Number net_builtin.c getpeer verification of source","tags":["vdb-entry","technical-description"]},{"url":"https://vuldb.com/?ctiid.347334","name":"VDB-347334 | CTI Indicators (IOB, IOC, IOA)","tags":["signature","permissions-required"]},{"url":"https://vuldb.com/?submit.755450","name":"Submit #755450 | Cesanta Mongoose Embedded Web Server 7.20 Improper Validation of Specified Index, Position, or Offset in I","tags":["third-party-advisory"]},{"url":"https://github.com/dwBruijn/CVEs/blob/main/Mongoose/tcp_rst.md","tags":["related"]},{"url":"https://github.com/dwBruijn/CVEs/blob/main/Mongoose/tcp_rst.md#poc","tags":["exploit"]}],"metrics":[{"cvssV4_0":{"version":"4.0","baseScore":6.3,"vectorString":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P","baseSeverity":"MEDIUM"}},{"cvssV3_1":{"version":"3.1","baseScore":3.7,"vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L/E:P/RL:X/RC:R","baseSeverity":"LOW"}},{"cvssV3_0":{"version":"3.0","baseScore":3.7,"vectorString":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L/E:P/RL:X/RC:R","baseSeverity":"LOW"}},{"cvssV2_0":{"version":"2.0","baseScore":2.6,"vectorString":"AV:N/AC:H/Au:N/C:N/I:N/A:P/E:POC/RL:ND/RC:UR"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-940","type":"CWE","lang":"en","description":"Improper Verification of Source of a Communication Channel"}]}],"providerMetadata":{"shortName":"VulDB","orgId":"1af790b2-7ee1-4545-860a-a788eba489b5","dateUpdated":"2026-02-23T02:32:07.568Z"},"timeline":[{"time":"2026-02-22T00:00:00.000Z","lang":"en","value":"Advisory disclosed"},{"time":"2026-02-22T01:00:00.000Z","lang":"en","value":"VulDB entry created"},{"time":"2026-02-22T09:02:38.000Z","lang":"en","value":"VulDB entry last update"}],"credits":[{"lang":"en","value":"dwbruijn (VulDB User)","type":"reporter"}],"tags":["x_open-source"]},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-02-23T13:32:47.660229Z","id":"CVE-2026-2967","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-02-23T13:32:57.830Z"}}]}}}