CVE Catalog

CVE-2026-80760

Unknown
Published: Translated: NVD NIST

Summary

In the Linux kernel, the Bluetooth MGMT handler lacks an upper bound for params_len in HCI_CMD_SYNC. params_len can exceed 255, leading to a mismatch with the plen field in the HCI header and potentially causing the controller to interpret trailing bytes as the start of the next packet.

Risk Assessment

A local user with access to the mgmt socket could send a malicious command, potentially leading to malfunction of the Bluetooth controller or a system crash.

Recommendation

Apply the Linux kernel update containing the fix that rejects params_len greater than 255.

Other vulnerabilities in Linux kernel

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Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: MGMT: reject HCI_CMD_SYNC params_len above 255 mgmt_hci_cmd_sync() checks that the message length agrees with params_len but puts no upper bound on it. params_len is __le16 while the parameter length in the HCI command header is a u8: struct hci_command_hdr { __le16 opcode; __u8 plen; } __packed; hci_cmd_sync_alloc() assigns one to the other: hdr->plen = plen; if (plen) skb_put_data(skb, param, plen); so a params_len of 256 leaves plen at 0 while all 256 bytes are still appended. The frame handed to the driver then declares no parameters and carries 256 of them. On a length framed transport such as H:4 the controller takes the trailing bytes as the start of the next packet. The mgmt socket MTU is HCI_MAX_FRAME_SIZE, so params_len can reach about 1KB this way. Commit 03f1700b9b4d ("Bluetooth: MGMT: reject malformed HCI_CMD_SYNC commands") only made params_len agree with the message length, a value that fits the message but not the header field is still accepted. Reject params_len that does not fit the header field.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS