CVE-2026-97977 — Bluetooth: btusb: Fix UAF of btusb_data by rx_work
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btusb: Fix UAF of btusb_data by rx_work btusb_close() and btusb_flush() cancel data->rx_work with the asynchronous cancel_delayed_work(), so if btusb_rx_work() is already running on another CPU it keeps running after the cancel returns. btusb_disconnect() calls hci_unregister_dev(), which invokes btusb_close(), and then frees the btusb_data. A still running btusb_rx_work() then dereferences the freed data: while ((skb = skb_dequeue(&data->acl_q))) data->recv_acl(data->hdev, skb); Use cancel_delayed_work_sync() instead. In btusb_close() the cancel also has to happen after btusb_stop_traffic(), otherwise an URB completion racing with the cancel can requeue the work right after it has been waited for.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+1
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux | ≥ 800fe5ec302e1ebbf5e3f891f886deecd49c7132 and < fc654a72a8d979db15e2773a481e931abaf5a9e8≥ 800fe5ec302e1ebbf5e3f891f886deecd49c7132 and < 5242050195a711e9cd6a9935f689ab6656b94a91≥ 800fe5ec302e1ebbf5e3f891f886deecd49c7132 and < 472d005622525b7be155cac99dde2252b0163bd1≥ 800fe5ec302e1ebbf5e3f891f886deecd49c7132 and < 93b59937bda3fffc6386c79f5544a39bc680c8e8≥ 800fe5ec302e1ebbf5e3f891f886deecd49c7132 and < fa391adb9c755515a89993634745e9079e5ef37c≥ 800fe5ec302e1ebbf5e3f891f886deecd49c7132 and < 1c12c3117639e78940959d956519c758c57d0849version 5.17 | Vulnerable | CVE Program (cve.org) e CISA ADP |
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Not enough vector or weakness data: use the affected application’s logs as a starting point.
Timeline
What happened to this CVE, newest first.
- 2026
- Record published
- Affected products added · linux/linux
- Source status changed · → Received
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
6 on the record
- git.kernel.org/stable/c/472d005622525b7be155cac99dde2252b0163bd1
- git.kernel.org/stable/c/fc654a72a8d979db15e2773a481e931abaf5a9e8
- git.kernel.org/stable/c/1c12c3117639e78940959d956519c758c57d0849
- git.kernel.org/stable/c/93b59937bda3fffc6386c79f5544a39bc680c8e8
- git.kernel.org/stable/c/5242050195a711e9cd6a9935f689ab6656b94a91
- git.kernel.org/stable/c/fa391adb9c755515a89993634745e9079e5ef37c
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 1d
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 1d
- Unknown CVE-2026-98431 RDMA/uverbs: Fix mmap_lock/disassociation_lock circular dependency 2d
- Unknown CVE-2026-98430 RDMA/efa: Keep admin queues alive while IRQ is registered 2d
- Unknown CVE-2026-98429 RDMA/efa: Keep EQ resources alive while IRQ is registered 2d
- Unknown CVE-2026-98428 ALSA: usb: 6fire: Avoid embedded URBs 2d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No CVSS score published by NVD, the CNA, CISA or GitHub so far.
- No fixed version, patch or mitigation documented.
- No CISA SSVC assessment.
- No CWE classification.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-97977 is "Bluetooth: btusb: Fix UAF of btusb_data by rx_work", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.17% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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