CVE-2026-43059: linux Use After Free

Vulnerability summary

CVE-2026-43059 is a high (CVSS 7.8) Use After Free vulnerability in linux. EPSS estimates a 0.18% chance of exploitation in the next 30 days, higher than 6.6% of scored vulnerabilities.

Timeline

1. 05-05-2026
   PublishedVulnerability first disclosed.
2. 21-10-2026
   Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: MGMT: Fix list corruption and UAF in command complete handlers Commit 302a1f674c00 ("Bluetooth: MGMT: Fix possible UAFs") introduced mgmt_pending_valid(), which not only validates the pending command but also unlinks it from the pending list if it is valid. This change in semantics requires updates to several completion handlers to avoid list corruption and memory safety issues. This patch addresses two left-over issues from the aforementioned rework: 1. In mgmt_add_adv_patterns_monitor_complete(), mgmt_pending_remove() is replaced with mgmt_pending_free() in the success path. Since mgmt_pending_valid() already unlinks the command at the beginning of the function, calling mgmt_pending_remove() leads to a double list_del() and subsequent list corruption/kernel panic. 2. In set_mesh_complete(), the use of mgmt_pending_foreach() in the error path is removed. Since the current command is already unlinked by mgmt_pending_valid(), this foreach loop would incorrectly target other pending mesh commands, potentially freeing them while they are still being processed concurrently (leading to UAFs). The redundant mgmt_cmd_status() is also simplified to use cmd->opcode directly.

• CWE-416Use After FreeThe product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.