CVE-2026-53254 PUBLISHED

Bluetooth: RFCOMM: validate skb length in MCC handlers

Assigner: Linux
Reserved: 09.06.2026 Published: 25.06.2026 Updated: 25.06.2026

In the Linux kernel, the following vulnerability has been resolved:

Bluetooth: RFCOMM: validate skb length in MCC handlers

The RFCOMM MCC handlers cast skb->data to protocol-specific structs without validating skb->len first. A malicious remote device can send truncated MCC frames and trigger out-of-bounds reads in these handlers.

Fix this by using skb_pull_data() to validate and access the required data before dereferencing it.

rfcomm_recv_rpn() requires special handling since ETSI TS 07.10 allows 1-byte RPN requests. Handle this by validating only the DLCI byte first, and validating the full struct only when len > 1.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to 7c15c7c2878957cbfed93bcc29c13fdace464254 (excl.)
  • affected from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to 0d637136ce89f9a2309b2c3502402ce400dab0ef (excl.)
  • affected from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to 98377e6b1a1a56561ec66a181573ea2b61b2079e (excl.)
  • affected from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to 1b070ac9e99c2c2c3a8112943ca98ab6fca7f10c (excl.)
  • affected from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to 3eabc6d47a0ad22b053329997aaf0ec1e581e392 (excl.)
  • affected from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to 08b9c1fbe78f4ad3f6250c6541cfaabdbeb81997 (excl.)
  • affected from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 to 23882b828c3c8c51d0c946446a396b10abb3b16b (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 2.6.12 is affected
  • unaffected from 0 to 2.6.12 (excl.)
  • unaffected from 5.15.210 to 5.15.* (incl.)
  • unaffected from 6.1.176 to 6.1.* (incl.)
  • unaffected from 6.6.143 to 6.6.* (incl.)
  • unaffected from 6.12.94 to 6.12.* (incl.)
  • unaffected from 6.18.36 to 6.18.* (incl.)
  • unaffected from 7.0.13 to 7.0.* (incl.)
  • unaffected from 7.1 to * (incl.)

References