{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-63975", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T07:54:57.024Z", "datePublished": "2026-07-19T14:56:00.662Z", "dateUpdated": "2026-08-05T12:37:46.003Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:37:46.003Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: Fix possible crash on l2cap_ecred_conn_rsp\n\nIf dcid is received for an already-assigned destination CID the spec\nrequires that both channels to be discarded, but calling l2cap_chan_del\nmay invalidate the tmp cursor created by list_for_each_entry_safe and\nin fact it is the wrong procedure as the chan->dcid may be assigned\npreviously it really needs to be disconnected.\n\nCalling l2cap_chan_clone directly may still lead to l2cap_chan_del so\ninstead schedule l2cap_chan_timeout with delay 0 to close the channel\nasynchronously." } ], "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": "AV:A - The bug is reached when a remote Bluetooth LE peer sends a crafted L2CAP_ECRED_CONN_RSP on the LE signaling channel, processed via hci_recv_frame → l2cap_recv_acldata → l2cap_le_sig_channel → l2cap_ecred_conn_rsp. Bluetooth is Adjacent per kernel CVSS guidance.\nAC:L - An adjacent attacker who establishes a BLE ACL link can reliably trigger this by first creating an L2CAP channel with a chosen DCID (via ECRED_CONN_REQ SCIDs) and then sending a connection response reusing that DCID for a pending outgoing ECRED connection; no race or rare layout is required.\nPR:N - Exploitation requires only the ability to act as a remote Bluetooth peer on an established ACL connection; no local shell access, capabilities, or root on the victim system is needed.\nUI:N - The malicious signaling traffic is delivered entirely by the remote attacker once a BLE link exists; no additional victim-side file open, mount, or application action beyond normal Bluetooth connectivity is required to reach the vulnerable handler.\nS:U - The failure is a kernel L2CAP channel-list use-after-free and crash within the Bluetooth stack on the victim host; it does not cross a VM, container, or IOMMU security boundary.\nC:H - Calling l2cap_chan_del() on the original channel during list_for_each_entry_safe can free the saved tmp list node, causing a use-after-free on struct l2cap_chan when iteration continues; UAF is scored as High confidentiality impact.\nI:H - The same iterator invalidation frees and later dereferences l2cap_chan objects under attacker-influenced connection state, providing a heap UAF primitive that can be groomed toward arbitrary memory corruption and code execution.\nA:H - The bug reliably produces kernel list corruption and use-after-free in softirq/context Bluetooth receive path, leading to kernel oops or panic and denial of service on phones, laptops, and embedded devices with Bluetooth enabled." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/bluetooth/l2cap_core.c" ], "versions": [ { "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "3c8eaa91eb433c450426539290be4ffe282e9f00", "status": "affected", "versionType": "git" }, { "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "ecfed1e0d8efecad6737a0d83e21d2fd021d8c48", "status": "affected", "versionType": "git" }, { "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "e6833e737a51db1e5ea0401322acf5e22abd8be6", "status": "affected", "versionType": "git" }, { "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "6319b38fe69f56ed95680ade485b957a53fff642", "status": "affected", "versionType": "git" }, { "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "291eec1041c918c460dc9702e44edd17794b4a4b", "status": "affected", "versionType": "git" }, { "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "41e29548b5e8b5e5fcf708786b3bea67cab107fa", "status": "affected", "versionType": "git" }, { "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "d153b8898c0051eb8b6a083b35cbe304a5886bd5", "status": "affected", "versionType": "git" }, { "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "41c2713b204e6cb6a94587bc6bf6935107df5479", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/bluetooth/l2cap_core.c" ], "versions": [ { "version": "5.7", "status": "affected" }, { "version": "0", "lessThan": "5.7", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.259", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.210", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.176", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.143", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.93", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.35", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0.12", "lessThanOrEqual": "7.0.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "5.10.259" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "5.15.210" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "6.1.176" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "6.6.143" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "6.12.93" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "6.18.35" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "7.0.12" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.7", "versionEndExcluding": "7.1" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/3c8eaa91eb433c450426539290be4ffe282e9f00" }, { "url": "https://git.kernel.org/stable/c/ecfed1e0d8efecad6737a0d83e21d2fd021d8c48" }, { "url": "https://git.kernel.org/stable/c/e6833e737a51db1e5ea0401322acf5e22abd8be6" }, { "url": "https://git.kernel.org/stable/c/6319b38fe69f56ed95680ade485b957a53fff642" }, { "url": "https://git.kernel.org/stable/c/291eec1041c918c460dc9702e44edd17794b4a4b" }, { "url": "https://git.kernel.org/stable/c/41e29548b5e8b5e5fcf708786b3bea67cab107fa" }, { "url": "https://git.kernel.org/stable/c/d153b8898c0051eb8b6a083b35cbe304a5886bd5" }, { "url": "https://git.kernel.org/stable/c/41c2713b204e6cb6a94587bc6bf6935107df5479" } ], "title": "Bluetooth: L2CAP: Fix possible crash on l2cap_ecred_conn_rsp", "x_generator": { "engine": "bippy-1.2.0" } } } }