{"id":"CVE-2026-12221","state":"PUBLISHED","title":"Yealink SIP-T46U Firmware Chunk Upload upgrade sprintf stack-based overflow","description":"A vulnerability was found in Yealink SIP-T46U 108.86.0.118. This impacts the function sprintf of the file /api/upgrade/upgrade of the component Firmware Chunk Upload Handler. Performing a manipulation of the argument uid/start_offset results in stack-based buffer overflow. The attack needs to be approached within the local network. The exploit has been made public and could be used. The vendor was contacted early about this disclosure and is working on a patch to fix it.","publishedAt":"2026-06-15T05:00:10.661Z","updatedAt":"2026-06-27T05:45:23.320Z","severity":{"score":8.6,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:A/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P","source":"VulDB"},"assigner":"VulDB","products":["Yealink SIP-T46U"],"affected":[{"vendor":"Yealink","product":"SIP-T46U","versions":[{"version":"108.86.0.118","status":"affected"}],"cpes":["cpe:2.3:a:yealink:sip-t46u:*:*:*:*:*:*:*:*"],"modules":["Firmware Chunk Upload Handler"]}],"references":["https://vuldb.com/vuln/370864","https://vuldb.com/vuln/370864/cti","https://vuldb.com/cve/CVE-2026-12221","https://vuldb.com/submit/834207","http://cdn2.v50to.cc/T46U/T46U_mod_upgrade_Upgrade_chunk_stack_overflow.zip"],"weaknesses":["CWE-121","CWE-119"],"ingestedAt":"2026-10-29T20:10:52.580Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/12xxx/CVE-2026-12221.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-12221","state":"PUBLISHED","datePublished":"2026-06-15T05:00:10.661Z","dateUpdated":"2026-06-27T05:45:23.320Z","assignerShortName":"VulDB","assignerOrgId":"1af790b2-7ee1-4545-860a-a788eba489b5","dateReserved":"2026-06-14T13:54:18.805Z"},"containers":{"cna":{"title":"Yealink SIP-T46U Firmware Chunk Upload upgrade sprintf stack-based overflow","descriptions":[{"lang":"en","value":"A vulnerability was found in Yealink SIP-T46U 108.86.0.118. This impacts the function sprintf of the file /api/upgrade/upgrade of the component Firmware Chunk Upload Handler. Performing a manipulation of the argument uid/start_offset results in stack-based buffer overflow. The attack needs to be approached within the local network. The exploit has been made public and could be used. The vendor was contacted early about this disclosure and is working on a patch to fix it."}],"affected":[{"vendor":"Yealink","product":"SIP-T46U","versions":[{"version":"108.86.0.118","status":"affected"}],"cpes":["cpe:2.3:a:yealink:sip-t46u:*:*:*:*:*:*:*:*"],"modules":["Firmware Chunk Upload Handler"]}],"references":[{"url":"https://vuldb.com/vuln/370864","name":"VDB-370864 | Yealink SIP-T46U Firmware Chunk Upload upgrade sprintf stack-based overflow","tags":["vdb-entry","technical-description"]},{"url":"https://vuldb.com/vuln/370864/cti","name":"VDB-370864 | CTI Indicators (IOB, IOC, IOA)","tags":["signature","permissions-required"]},{"url":"https://vuldb.com/cve/CVE-2026-12221","name":"CVE-2026-12221 | CVE Analysis and Report","tags":["third-party-advisory"]},{"url":"https://vuldb.com/submit/834207","name":"Submit #834207 | yealink T46U 108.86.0.118 Stack-based Buffer Overflow","tags":["third-party-advisory"]},{"url":"http://cdn2.v50to.cc/T46U/T46U_mod_upgrade_Upgrade_chunk_stack_overflow.zip","tags":["broken-link","exploit","patch"]}],"metrics":[{"cvssV4_0":{"version":"4.0","baseScore":8.6,"vectorString":"CVSS:4.0/AV:A/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P","baseSeverity":"HIGH"}},{"cvssV3_1":{"version":"3.1","baseScore":8,"vectorString":"CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:C","baseSeverity":"HIGH"}},{"cvssV3_0":{"version":"3.0","baseScore":8,"vectorString":"CVSS:3.0/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:C","baseSeverity":"HIGH"}},{"cvssV2_0":{"version":"2.0","baseScore":7.7,"vectorString":"AV:A/AC:L/Au:S/C:C/I:C/A:C/E:POC/RL:ND/RC:C"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-121","type":"CWE","lang":"en","description":"Stack-based Buffer Overflow"}]},{"descriptions":[{"cweId":"CWE-119","type":"CWE","lang":"en","description":"Memory Corruption"}]}],"providerMetadata":{"shortName":"VulDB","orgId":"1af790b2-7ee1-4545-860a-a788eba489b5","dateUpdated":"2026-06-27T05:45:23.320Z"},"timeline":[{"time":"2026-06-14T00:00:00.000Z","lang":"en","value":"Advisory disclosed"},{"time":"2026-06-14T02:00:00.000Z","lang":"en","value":"VulDB entry created"},{"time":"2026-06-27T07:47:33.000Z","lang":"en","value":"VulDB entry last update"}],"credits":[{"lang":"en","value":"CookedMelon (VulDB User)","type":"reporter"},{"lang":"en","value":"VulDB CNA Team","type":"coordinator"}]},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-06-15T12:50:29.215688Z","id":"CVE-2026-12221","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-06-15T12:50:45.903Z"}}]}}}