Integer underflow in Linux kernel - CVE-2026-68479
Published: August 16, 2026
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to an integer underflow leading to out-of-bounds read and out-of-bounds write in rtlbt_parse_firmware() when parsing a malformed Bluetooth firmware patch during Bluetooth setup. A local user can supply a specially crafted firmware patch to cause a denial of service.
The issue can be triggered by a firmware patch shorter than the version field, and arithmetic wraparound may affect 32-bit architectures.
Affected software
Ubuntu
linux-nvidia (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
How to mitigate CVE-2026-68479
linux-nvidia (Ubuntu package) - addressed in versions 5.15.0-1112.113, 5.15.0.1112.112
linux-gcp-7.0 (Ubuntu package) - addressed in versions 7.0.0-38.38~24.04.4, 7.0.0-1013.13~24.04.1, 7.0.0-1014.14~24.04.1
linux-azure-7.0 (Ubuntu package) - addressed in versions 7.0.0-1016.16~24.04.1, 7.0.0-1017.17~24.04.1
External References
- https://git.kernel.org/stable/c/39e01b4addfbbe177567d6ed1dfb81f9cccb19e6
- https://git.kernel.org/stable/c/609c5b04a28dc1b0f3af6a7bc93055135b2d2059
- https://git.kernel.org/stable/c/6744ab60dfac55d1df5733960aad5be300984301
- https://git.kernel.org/stable/c/68c5a2a19987c035eb129e627e579adafb04f637
- https://git.kernel.org/stable/c/83534891c058ed71e251135072640911670869aa
- https://git.kernel.org/stable/c/a4cb830e0b55ac76c849fd7840afb251f4c028fa
- https://git.kernel.org/stable/c/bda3c598ade6ea03884074b91e31608326684921
- https://git.kernel.org/stable/c/f1ca750c0510bdbb504bf084d2f196ef2af92ea6