CVE-2026-63976

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: l2cap: clear chan->ident on ECRED reconfiguration success l2cap_ecred_reconf_rsp() returns early on success without clearing chan->ident. Every other L2CAP response handler (l2cap_ecred_conn_rsp, l2cap_le_connect_rsp, l2cap_config_rsp) clears chan->ident after a successful transaction to prevent the channel from matching subsequent responses with the recycled ident value. A remote attacker that completed a reconfiguration as the peer can replay a failure response with the stale ident, causing the kernel to match and destroy the already-established channel via l2cap_chan_del(chan, ECONNRESET). Clear chan->ident for all matching channels on success, and harden the failure path by using l2cap_chan_hold_unless_zero() consistent with other L2CAP handlers (l2cap_le_command_rej, __l2cap_get_chan_by_ident).

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/00e1950716c6ed67d74777b2db286b0fa23b4be9
https://git.kernel.org/stable/c/3b5b5f423b4fd23404a393bda8adba3cd6f74ef1
https://git.kernel.org/stable/c/59f5ecf6ad5c4db6ae81965a96156954a3b0d89a
https://git.kernel.org/stable/c/8e7977afaef37c6bd2b2654f1bce6ab40d471147
https://git.kernel.org/stable/c/ae0152d77d101c920769934fb102b18de0c6f526
https://git.kernel.org/stable/c/c2afd2613fda90107c5e2fe8e855627451749c78
https://git.kernel.org/stable/c/cc2b4f749de09975bfa06e58bbbad2f6acd4c79c
https://git.kernel.org/stable/c/f39049304ba655ffcbb92edbdf8c51a1f1210bed

Configurations

No configuration.

History

19 Oct 2026, 21:17

Type	Values Removed	Values Added
CWE		CWE-694

Information

Published : 2026-07-19 16:17

Updated : 2026-10-19 21:17

NVD link : CVE-2026-63976

Mitre link : CVE-2026-63976

CVE.ORG link : CVE-2026-63976

JSON object : View

Products Affected

No product.

CWE

CWE-694

Use of Multiple Resources with Duplicate Identifier

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"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "59f5ecf6ad5c4db6ae81965a96156954a3b0d89a", "versionType": "git"}, {"status": "affected", "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "ae0152d77d101c920769934fb102b18de0c6f526", "versionType": "git"}, {"status": "affected", "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "c2afd2613fda90107c5e2fe8e855627451749c78", "versionType": "git"}, {"status": "affected", "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "cc2b4f749de09975bfa06e58bbbad2f6acd4c79c", "versionType": "git"}, {"status": "affected", "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "3b5b5f423b4fd23404a393bda8adba3cd6f74ef1", "versionType": "git"}, {"status": "affected", "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "f39049304ba655ffcbb92edbdf8c51a1f1210bed", "versionType": "git"}, {"status": "affected", "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "8e7977afaef37c6bd2b2654f1bce6ab40d471147", "versionType": "git"}, {"status": "affected", "version": "15f02b91056253e8cdc592888f431da0731337b8", "lessThan": "00e1950716c6ed67d74777b2db286b0fa23b4be9", "versionType": "git"}], "programFiles": ["net/bluetooth/l2cap_core.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "5.7"}, {"status": "unaffected", "version": "0", "lessThan": "5.7", "versionType": "semver"}, {"status": "unaffected", "version": "5.10.259", "versionType": "semver", "lessThanOrEqual": "5.10.*"}, {"status": "unaffected", "version": "5.15.210", "versionType": "semver", "lessThanOrEqual": "5.15.*"}, {"status": "unaffected", "version": "6.1.176", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"status": "unaffected", "version": "6.6.143", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.12.93", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.18.35", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "7.0.12", "versionType": "semver", "lessThanOrEqual": "7.0.*"}, {"status": "unaffected", "version": "7.1", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["net/bluetooth/l2cap_core.c"], "defaultStatus": "affected"}]}], "published": "2026-07-19T16:17:16.733", "references": [{"url": "https://git.kernel.org/stable/c/00e1950716c6ed67d74777b2db286b0fa23b4be9", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/3b5b5f423b4fd23404a393bda8adba3cd6f74ef1", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/59f5ecf6ad5c4db6ae81965a96156954a3b0d89a", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/8e7977afaef37c6bd2b2654f1bce6ab40d471147", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/ae0152d77d101c920769934fb102b18de0c6f526", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/c2afd2613fda90107c5e2fe8e855627451749c78", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/cc2b4f749de09975bfa06e58bbbad2f6acd4c79c", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/f39049304ba655ffcbb92edbdf8c51a1f1210bed", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Undergoing Analysis", "weaknesses": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "description": [{"lang": "en", "value": "CWE-694"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: l2cap: clear chan->ident on ECRED reconfiguration success\n\nl2cap_ecred_reconf_rsp() returns early on success without clearing\nchan->ident. Every other L2CAP response handler (l2cap_ecred_conn_rsp,\nl2cap_le_connect_rsp, l2cap_config_rsp) clears chan->ident after a\nsuccessful transaction to prevent the channel from matching subsequent\nresponses with the recycled ident value.\n\nA remote attacker that completed a reconfiguration as the peer can\nreplay a failure response with the stale ident, causing the kernel to\nmatch and destroy the already-established channel via\nl2cap_chan_del(chan, ECONNRESET).\n\nClear chan->ident for all matching channels on success, and harden the\nfailure path by using l2cap_chan_hold_unless_zero() consistent with\nother L2CAP handlers (l2cap_le_command_rej, __l2cap_get_chan_by_ident)."}], "lastModified": "2026-10-19T21:17:15.263", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}