{"id":"CVE-2026-23395","state":"PUBLISHED","title":"Bluetooth: L2CAP: Fix accepting multiple L2CAP_ECRED_CONN_REQ","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: Fix accepting multiple L2CAP_ECRED_CONN_REQ\n\nCurrently the code attempts to accept requests regardless of the\ncommand identifier which may cause multiple requests to be marked\nas pending (FLAG_DEFER_SETUP) which can cause more than\nL2CAP_ECRED_MAX_CID(5) to be allocated in l2cap_ecred_rsp_defer\ncausing an overflow.\n\nThe spec is quite clear that the same identifier shall not be used on\nsubsequent requests:\n\n'Within each signaling channel a different Identifier shall be used\nfor each successive request or indication.'\nhttps://www.bluetooth.com/wp-content/uploads/Files/Specification/HTML/Core-62/out/en/host/logical-link-control-and-adaptation-protocol-specification.html#UUID-32a25a06-4aa4-c6c7-77c5-dcfe3682355d\n\nSo this attempts to check if there are any channels pending with the\nsame identifier and rejects if any are found.","publishedAt":"2026-03-25T10:33:18.936Z","updatedAt":"2026-10-19T18:35:42.470Z","severity":{"score":8.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"15f02b91056253e8cdc592888f431da0731337b8","status":"affected","lessThan":"10a7a702542240d5edb2b39450ac951c59ccd009","versionType":"git"},{"version":"15f02b91056253e8cdc592888f431da0731337b8","status":"affected","lessThan":"46e5b71666fb7652082e4e214a3365f4b14f1dc3","versionType":"git"},{"version":"15f02b91056253e8cdc592888f431da0731337b8","status":"affected","lessThan":"fb4a3a26483f3ea2cd21c7a2f7c45d5670600465","versionType":"git"},{"version":"15f02b91056253e8cdc592888f431da0731337b8","status":"affected","lessThan":"2124d82fd25e1671bb3ceb37998af5aae5903e06","versionType":"git"},{"version":"15f02b91056253e8cdc592888f431da0731337b8","status":"affected","lessThan":"6b949a6b33cbdf621d9fc6f0c48ac00915dbf514","versionType":"git"},{"version":"15f02b91056253e8cdc592888f431da0731337b8","status":"affected","lessThan":"8d0d94f8ba5b3a0beec3b0da558b9bea48018117","versionType":"git"},{"version":"15f02b91056253e8cdc592888f431da0731337b8","status":"affected","lessThan":"e72ee455297b794b852e5cea8d2d7bb17312172a","versionType":"git"},{"version":"15f02b91056253e8cdc592888f431da0731337b8","status":"affected","lessThan":"5b3e2052334f2ff6d5200e952f4aa66994d09899","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/bluetooth/l2cap_core.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.7","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.7","versionType":"semver"},{"version":"5.10.253","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.203","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.167","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.130","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.78","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.20","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.10","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/bluetooth/l2cap_core.c"]}],"references":["https://git.kernel.org/stable/c/10a7a702542240d5edb2b39450ac951c59ccd009","https://git.kernel.org/stable/c/46e5b71666fb7652082e4e214a3365f4b14f1dc3","https://git.kernel.org/stable/c/fb4a3a26483f3ea2cd21c7a2f7c45d5670600465","https://git.kernel.org/stable/c/2124d82fd25e1671bb3ceb37998af5aae5903e06","https://git.kernel.org/stable/c/6b949a6b33cbdf621d9fc6f0c48ac00915dbf514","https://git.kernel.org/stable/c/8d0d94f8ba5b3a0beec3b0da558b9bea48018117","https://git.kernel.org/stable/c/e72ee455297b794b852e5cea8d2d7bb17312172a","https://git.kernel.org/stable/c/5b3e2052334f2ff6d5200e952f4aa66994d09899","https://cert-portal.siemens.com/productcert/html/ssa-784472.html"],"weaknesses":["CWE-20"],"ingestedAt":"2026-10-29T20:11:21.040Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/23xxx/CVE-2026-23395.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-23395","state":"PUBLISHED","datePublished":"2026-03-25T10:33:18.936Z","dateUpdated":"2026-10-19T18:35:42.470Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-01-13T15:37:46.011Z"},"containers":{"cna":{"title":"Bluetooth: L2CAP: Fix accepting multiple L2CAP_ECRED_CONN_REQ","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: Fix accepting multiple L2CAP_ECRED_CONN_REQ\n\nCurrently the code attempts to accept requests regardless of the\ncommand identifier which may cause multiple requests to be marked\nas pending (FLAG_DEFER_SETUP) which can cause more than\nL2CAP_ECRED_MAX_CID(5) to be allocated in l2cap_ecred_rsp_defer\ncausing an overflow.\n\nThe spec is quite clear that the same identifier shall not be used on\nsubsequent requests:\n\n'Within each signaling channel a different Identifier shall be used\nfor each successive request or indication.'\nhttps://www.bluetooth.com/wp-content/uploads/Files/Specification/HTML/Core-62/out/en/host/logical-link-control-and-adaptation-protocol-specification.html#UUID-32a25a06-4aa4-c6c7-77c5-dcfe3682355d\n\nSo this attempts to check if there are any channels pending with the\nsame identifier and rejects if any are found."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"15f02b91056253e8cdc592888f431da0731337b8","status":"affected","lessThan":"10a7a702542240d5edb2b39450ac951c59ccd009","versionType":"git"},{"version":"15f02b91056253e8cdc592888f431da0731337b8","status":"affected","lessThan":"46e5b71666fb7652082e4e214a3365f4b14f1dc3","versionType":"git"},{"version":"15f02b91056253e8cdc592888f431da0731337b8","status":"affected","lessThan":"fb4a3a26483f3ea2cd21c7a2f7c45d5670600465","versionType":"git"},{"version":"15f02b91056253e8cdc592888f431da0731337b8","status":"affected","lessThan":"2124d82fd25e1671bb3ceb37998af5aae5903e06","versionType":"git"},{"version":"15f02b91056253e8cdc592888f431da0731337b8","status":"affected","lessThan":"6b949a6b33cbdf621d9fc6f0c48ac00915dbf514","versionType":"git"},{"version":"15f02b91056253e8cdc592888f431da0731337b8","status":"affected","lessThan":"8d0d94f8ba5b3a0beec3b0da558b9bea48018117","versionType":"git"},{"version":"15f02b91056253e8cdc592888f431da0731337b8","status":"affected","lessThan":"e72ee455297b794b852e5cea8d2d7bb17312172a","versionType":"git"},{"version":"15f02b91056253e8cdc592888f431da0731337b8","status":"affected","lessThan":"5b3e2052334f2ff6d5200e952f4aa66994d09899","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/bluetooth/l2cap_core.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.7","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.7","versionType":"semver"},{"version":"5.10.253","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.203","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.167","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.130","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.78","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.20","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.10","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/bluetooth/l2cap_core.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/10a7a702542240d5edb2b39450ac951c59ccd009"},{"url":"https://git.kernel.org/stable/c/46e5b71666fb7652082e4e214a3365f4b14f1dc3"},{"url":"https://git.kernel.org/stable/c/fb4a3a26483f3ea2cd21c7a2f7c45d5670600465"},{"url":"https://git.kernel.org/stable/c/2124d82fd25e1671bb3ceb37998af5aae5903e06"},{"url":"https://git.kernel.org/stable/c/6b949a6b33cbdf621d9fc6f0c48ac00915dbf514"},{"url":"https://git.kernel.org/stable/c/8d0d94f8ba5b3a0beec3b0da558b9bea48018117"},{"url":"https://git.kernel.org/stable/c/e72ee455297b794b852e5cea8d2d7bb17312172a"},{"url":"https://git.kernel.org/stable/c/5b3e2052334f2ff6d5200e952f4aa66994d09899"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":8.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"Bluetooth L2CAP stack buffer overflow via duplicate ECRED connection requests with same identifier. l2cap_ecred_rsp_defer() writes past L2CAP_ECRED_MAX_CID(5) array bound on the stack. Triggered over the air by a nearby device, no pairing or authentication needed."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T12:21:25.659Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"5.10.253"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"5.15.203"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"6.1.167"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"6.6.130"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"6.12.78"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"6.18.20"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"6.19.10"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.7","versionEndExcluding":"7.0"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"affected":[{"vendor":"Siemens","product":"SIMATIC S7-1500 TM MFP - GNU/Linux subsystem","defaultStatus":"unknown","versions":[{"version":"0","status":"affected","lessThan":"*","versionType":"custom"}]}],"references":[{"url":"https://cert-portal.siemens.com/productcert/html/ssa-784472.html"}],"providerMetadata":{"shortName":"siemens-SADP","orgId":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e","dateUpdated":"2026-10-15T01:14:45.143Z"},"x_adpType":"supplier"},{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-23395","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T15:07:40.817542Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-20","lang":"en","type":"CWE","description":"CWE-20 Improper Input Validation"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-19T18:35:42.470Z"}}]}}}