Bluetooth: RFCOMM: validate skb length in MCC handlers

Summary

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.

Timeline

1. Jun 25, 2026, 8:39 AM UTCCVE published
2. Oct 16, 2026, 3:27 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: no · Technical impact: partial

3. Oct 19, 2026, 7:57 PM UTCRecord last updated

Affected versions

• Linux Linux

  From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in 7c15c7c2878957cbfed93bcc29c13fdace464254; From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in 0d637136ce89f9a2309b2c3502402ce400dab0ef; From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in 98377e6b1a1a56561ec66a181573ea2b61b2079e; From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in 1b070ac9e99c2c2c3a8112943ca98ab6fca7f10c; From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in 3eabc6d47a0ad22b053329997aaf0ec1e581e392; From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in 08b9c1fbe78f4ad3f6250c6541cfaabdbeb81997; From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in 23882b828c3c8c51d0c946446a396b10abb3b16b

• Linux Linux

  2.6.12

• KernelLinux

  From 2.6.12 · fixed in 5.15.210; From 5.16.0 · fixed in 6.1.176; From 6.2.0 · fixed in 6.6.143; From 6.7.0 · fixed in 6.12.94; From 6.13.0 · fixed in 6.18.36; From 6.19.0 · fixed in 7.0.13

References 7