Bluetooth: btrtl: validate firmware patch bounds

Summary

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btrtl: validate firmware patch bounds rtlbt_parse_firmware() copies patch_length - 4 bytes before appending the firmware version. A malformed firmware patch shorter than the version field can make this subtraction underflow and turn the copy into an oversized read and write during Bluetooth setup. The existing patch_offset + patch_length check can also wrap on 32-bit architectures. Validate the patch length and range without arithmetic overflow before allocating or copying the patch.

Timeline

1. Aug 15, 2026, 5:51 AM UTCCVE published
2. Oct 16, 2026, 3:49 PM UTCCISA SSVC assessment

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

3. Oct 19, 2026, 9:09 PM UTCRecord last updated

Affected versions

• Linux Linux

  From db33c77dddc2ed2cff3061d0b096a9f5ab0c3647 · fixed in 39e01b4addfbbe177567d6ed1dfb81f9cccb19e6; From db33c77dddc2ed2cff3061d0b096a9f5ab0c3647 · fixed in bda3c598ade6ea03884074b91e31608326684921; From db33c77dddc2ed2cff3061d0b096a9f5ab0c3647 · fixed in a4cb830e0b55ac76c849fd7840afb251f4c028fa; From db33c77dddc2ed2cff3061d0b096a9f5ab0c3647 · fixed in 68c5a2a19987c035eb129e627e579adafb04f637; From db33c77dddc2ed2cff3061d0b096a9f5ab0c3647 · fixed in 83534891c058ed71e251135072640911670869aa; From db33c77dddc2ed2cff3061d0b096a9f5ab0c3647 · fixed in 6744ab60dfac55d1df5733960aad5be300984301; From db33c77dddc2ed2cff3061d0b096a9f5ab0c3647 · fixed in f1ca750c0510bdbb504bf084d2f196ef2af92ea6; From db33c77dddc2ed2cff3061d0b096a9f5ab0c3647 · fixed in 609c5b04a28dc1b0f3af6a7bc93055135b2d2059

• Linux Linux

  4.2

• KernelLinux

  From 4.2.0 · fixed in 5.10.261; From 5.11.0 · fixed in 5.15.212; From 5.16.0 · fixed in 6.1.178; From 6.2.0 · fixed in 6.6.145; From 6.7.0 · fixed in 6.12.97; From 6.13.0 · fixed in 6.18.40; From 6.19.0 · fixed in 7.1.5

References 8