CVE-2026-43017: Bluetooth: MGMT: validate mesh send advertising payload length

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-01 · updated 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: MGMT: validate mesh send advertising payload length mesh_send() currently bounds MGMT_OP_MESH_SEND by total command length, but it never verifies that the bytes supplied for the flexible adv_data[] array actually match the embedded adv_data_len field. MGMT_MESH_SEND_SIZE only covers the fixed header, so a truncated command can still pass the existing 20..50 byte range check and later drive the async mesh send path past the end of the queued command buffer. Keep rejecting zero-length and oversized advertising payloads, but validate adv_data_len explicitly and require the command length to exactly match the flexible array size before queueing the request.

Affected products

Linux kernel: from 6.1 before 6.1.168; from 6.2 before 6.6.134; from 6.7 before 6.12.81; from 6.13 before 6.18.22; from 6.19 before 6.19.12; 7.0-rc1, 7.0-rc2, 7.0-rc3, 7.0-rc4, 7.0-rc5, 7.0-rc6 — fixed in 6.1.168, 6.12.81, 6.18.22, 6.19.12, 6.6.134

How to fix

Upgrade to a fixed version: Linux kernel 6.1.168, 6.12.81, 6.18.22, 6.19.12. Check the vendor advisory for mitigations.

References

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