CVE-2026-64404 (GCVE-0-2026-64404)

Vulnerability from cvelistv5 – Published: 2026-07-25 08:50 – Updated: 2026-08-17 04:55
VLAI
Title
Bluetooth: ISO: avoid NULL deref of conn in iso_conn_big_sync()
Summary
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ISO: avoid NULL deref of conn in iso_conn_big_sync() iso_conn_big_sync() drops the socket lock to call hci_get_route() and then re-acquires it, but dereferences iso_pi(sk)->conn->hcon afterwards without re-checking that conn is still valid. While the lock is dropped, the connection can be torn down under the same socket lock: iso_disconn_cfm() -> iso_conn_del() -> iso_chan_del() sets iso_pi(sk)->conn to NULL (and the broadcast teardown path can also clear conn->hcon on its own). When iso_conn_big_sync() re-acquires the lock and reads conn->hcon, conn may be NULL, causing a NULL pointer dereference (hcon is the first member of struct iso_conn). This path is reached from iso_sock_recvmsg() for a PA-sync broadcast sink socket (BT_SK_DEFER_SETUP | BT_SK_PA_SYNC), so the dropped-lock window can race with connection teardown driven by controller events. Re-validate iso_pi(sk)->conn and its hcon after re-acquiring the socket lock and bail out if the connection went away, as already done in the sibling iso_sock_rebind_bc().
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: cbe640d6cae590b9a7d81ce86fe9a90e83eec1d5 , < b3e647a4aa4d2d054f86a783f5c426035e1dc237 (git)
Affected: 7a17308c17880d259105f6e591eb1bc77b9612f0 , < b84eeb7636d6962dd882d5e0b31475e4f404313c (git)
Affected: 7a17308c17880d259105f6e591eb1bc77b9612f0 , < 01afd198c2c286cd3b81f44d4e33a2e638711550 (git)
Affected: 7a17308c17880d259105f6e591eb1bc77b9612f0 , < d5541eb148da72d5e0a1bca8ecd171f9fc8b366f (git)
Affected: 6.12.6 , < 6.12.96 (semver)
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Linux Linux Affected: 6.13
Unaffected: 0 , < 6.13 (semver)
Unaffected: 6.12.96 , ≤ 6.12.* (semver)
Unaffected: 6.18.39 , ≤ 6.18.* (semver)
Unaffected: 7.1.4 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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      "cve": "CVE-2026-64404",
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      "product_status:known_affected": "184",
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      "source": "Red Hat CSAF VEX",
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      "title": "kernel: Bluetooth: ISO: avoid NULL deref of conn in iso_conn_big_sync()",
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      "cve": "CVE-2026-64404",
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      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-64404",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-64404.json",
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}



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