CVE-2026-74509: linux
Vulnerability summary
CVE-2026-74509 is a high (CVSS 8.8) vulnerability in linux. EPSS estimates a 0.25% chance of exploitation in the next 30 days, higher than 15.2% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 8 · Related 7Timeline
- 15-08-2026PublishedVulnerability first disclosed.
- 16-10-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_sync: Fix advertising data UAFs hci_find_adv_instance() returns an adv_info pointer that is valid only while hdev->lock is held. The advertising command-sync paths perform instance lookups without that lock and, in some cases, retain the pointer while waiting for a controller response. An advertising termination event can therefore interleave as follows: hci_cmd_sync_work hci_rx_work hci_find_adv_instance() __hci_cmd_sync_status() wait for controller reply hci_dev_lock() hci_remove_adv_instance() kfree(adv) adv->scan_rsp_changed = false KASAN reported: BUG: KASAN: slab-use-after-free in hci_set_ext_scan_rsp_data_sync+0x2e1/0x300 Write of size 1 at addr ffff88810a45d21d by task kworker/u17:0/88 Workqueue: hci0 hci_cmd_sync_work Call Trace: hci_set_ext_scan_rsp_data_sync+0x2e1/0x300 hci_schedule_adv_instance_sync+0x390/0x4c0 hci_cmd_sync_work+0x173/0x300 Allocated by task 87: hci_add_adv_instance+0x538/0xac0 add_advertising+0x885/0x1160 Freed by task 89: kfree+0x131/0x3c0 hci_remove_adv_instance+0x1d8/0x3b0 hci_le_ext_adv_term_evt+0x17b/0x730 Protect the instance lookup and payload construction in the extended advertising, scan response, and periodic advertising data paths. Snapshot the advertising parameters under hdev->lock, but release the lock before waiting for the controller. Clear advertising-data dirty bits before issuing their commands and restore them after a failure using a fresh lookup. Likewise, update the reported transmit power through a fresh lookup after the parameter command completes. No adv_info pointer then survives an HCI command wait.
CVSS metrics
4 scores · 4 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated8.8HighCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated8.8HighCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- NVDNIST8.8HighCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.25%
Chance of exploitation in the next 30 days
Percentile
15%
Versus all other CVEs
30-day change
0.00 pp
From 0.25% on 20-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeNo weakness data has been published for this record.
Affected systems
Ubuntu154 products
- linuxAll versions (No fix recorded)
- linux-allwinner-5.19All versions (No fix recorded)
- linux-awsAll versions (No fix recorded)
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Debian2 products
- linux< 6.1.187-1 | < 6.12.105-1 | < 7.1.8-1
- linux-6.12< 6.12.107-1~deb12u1
Linux1 product
- linux≥ cba6b758711cab946c787f7c15be92cc749b8e1f, < 565971488191bf54a87a417abafab6ad0de72201 | ≥ cba6b758711cab946c787f7c15be92cc749b8e1f, < c4cec575a6d6f7c36808a3a0017b0675968bb06b | ≥ cba6b758711cab946c787f7c15be92cc749b8e1f, < 95cdcd8c82a501931fd3ae9b3811b0b6da167e94 | ≥ cba6b758711cab946c787f7c15be92cc749b8e1f, < eb1d8318764de7216e6dbba29a24d69f7ce51348 | ≥ cba6b758711cab946c787f7c15be92cc749b8e1f, < b16ebdbebd2d37f4cdc590bc3e9db71fe90350a3 | ≥ cba6b758711cab946c787f7c15be92cc749b8e1f, < cdc36db204ffd97b947d64374cf23a210dc74777 | 42fe380baaaccbe635c34ca07b29d19b9ec2498d | ≥ 5.15.210, < 5.16 | 5.17
3 vendors · 157 products
