CVE-2026-74537: Bluetooth: ISO: hold sk properly in iso_conn_ready
Greg Kroah-Hartman <[email protected]>
| Newsgroups | org.kernel.vger.linux-cve-announce |
|---|---|
| Message-ID | <2026081548-CVE-2026-74537-7d32@gregkh> |
From: Greg Kroah-Hartman <[email protected]> Description =========== In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ISO: hold sk properly in iso_conn_ready sk deref in iso_conn_ready must be done either under conn->lock, or holding a refcount, to avoid concurrent close. conn->sk is currently accessed without either: [Task 1] [Task 2] iso_sock_release iso_conn_ready sk = conn->sk lock_sock(sk) conn->sk = NULL lock_sock(sk) release_sock(sk) iso_sock_kill(sk) UAF on sk deref Fix possible UAF by holding sk refcount in iso_conn_ready(). Also recheck after lock_sock that the socket is still valid. Adjust locking so conn->sk is cleared only under lock_sock. The Linux kernel CVE team has assigned CVE-2026-74537 to this issue. Affected and fixed versions =========================== Issue introduced in 5.15 with commit 27c24fda62b601d6f9ca5e992502578c4310876f and fixed in 6.18.44 with commit 4e9b5e8669b3602a4e01b6d1e9539b72e42c84d5 Issue introduced in 5.15 with commit 27c24fda62b601d6f9ca5e992502578c4310876f and fixed in 7.1.8 with commit 1308d72903d792d10b82bc4ef08b8a4452308b04 Issue introduced in 5.15 with commit 27c24fda62b601d6f9ca5e992502578c4310876f and fixed in 7.2-rc6 with commit 0d255e63fcf3f13a570d7ac11678fa1164ac015c Please see https://www.kernel.org for a full list of currently supported kernel versions by the kernel community. Unaffected versions might change over time as fixes are backported to older supported kernel versions. The official CVE entry at https://cve.org/CVERecord/?id=CVE-2026-74537 will be updated if fixes are backported, please check that for the most up to date information about this issue. Affected files ============== The file(s) affected by this issue are: net/bluetooth/iso.c Mitigation ========== The Linux kernel CVE team recommends that you update to the latest stable kernel version for this, and many other bugfixes. Individual changes are never tested alone, but rather are part of a larger kernel release. Cherry-picking individual commits is not recommended or supported by the Linux kernel community at all. If however, updating to the latest release is impossible, the individual changes to resolve this issue can be found at these commits: https://git.kernel.org/stable/c/4e9b5e8669b3602a4e01b6d1e9539b72e42c84d5 https://git.kernel.org/stable/c/1308d72903d792d10b82bc4ef08b8a4452308b04 https://git.kernel.org/stable/c/0d255e63fcf3f13a570d7ac11678fa1164ac015c