Out-of-bounds write in Linux kernel - CVE-2026-64085
Published: July 20, 2026
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to an out-of-bounds write in adm1266_nvmem_read_blackbox() when processing device-supplied blackbox records. A local user can provide a device response with more than 64 bytes in a trailing record to cause a denial of service.
The issue occurs because the helper may write up to 255 bytes into a 64-byte record slot before the returned length is validated.
Affected software
Ubuntu
linux (Ubuntu package)
linux-aws (Ubuntu package)
linux-nvidia-tegra (Ubuntu package)
linux-nvidia-tegra-5.15 (Ubuntu package)
linux-intel-iot-realtime (Ubuntu package)
linux-intel-iotg (Ubuntu package)
linux-azure (Ubuntu package)
linux-azure-5.15 (Ubuntu package)
linux-gcp-5.15 (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-azure-fde (Ubuntu package)
linux-ibm (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-nvidia-bos (Ubuntu package)
How to mitigate CVE-2026-64085
linux (Ubuntu package) - addressed in versions 5.15.0.184.155, 5.15.0-184.194, 5.15.0-184.194~20.04.1, 5.15.0.186.166, 5.15.0-186.196, 5.15.0-186.196~20.04.1, 5.15.0.1075.78, 5.15.0-1075.79, 5.15.0.1095.94, 5.15.0-1095.103, 5.15.0.1104.100, 5.15.0-1104.109, 5.15.0.1108.107, 5.15.0-1108.114, 5.15.0.1111.115, 5.15.0-1111.120+fips1, 5.15.0.1112.102, 5.15.0.1112.109, 5.15.0-1112.122, 5.15.0-1112.122+fips1
linux-aws (Ubuntu package) - addressed in versions 5.15.0.186.109, 5.15.0-186.196+fips1, 5.15.0.1106.103, 5.15.0-1106.110, 5.15.0.1107.107, 5.15.0-1107.108, 5.15.0.1112.108, 5.15.0.1112.115, 5.15.0-1112.119, 5.15.0-1112.119+fips1, 5.15.0-1112.119~20.04.1, 7.0.0-1009.9, 7.0.0-1015.15
linux-nvidia-tegra (Ubuntu package) - addressed in versions 5.15.0-1053.53, 5.15.0.1053.55, 5.15.0.1064.64, 5.15.0-1064.66
linux-nvidia-tegra-5.15 (Ubuntu package) - update to 5.15.0-1064.66~20.04.1
linux-intel-iot-realtime (Ubuntu package) - addressed in versions 5.15.0-1104.106, 5.15.0.1104.108, 5.15.0-1107.113~20.04.1
linux-intel-iotg (Ubuntu package) - addressed in versions 5.15.0.1107.106, 5.15.0-1107.113
linux-azure (Ubuntu package) - addressed in versions 5.15.0.1109.105, 5.15.0-1109.115, 5.15.0.1117.115, 5.15.0-1117.126, 7.0.0-1009.9, 7.0.0-1010.10
linux-azure-5.15 (Ubuntu package) - addressed in versions 5.15.0-1109.115~20.04.1, 5.15.0-1117.126~20.04.1, 5.15.0-1117.126~20.04.2
linux-gcp-5.15 (Ubuntu package) - update to 5.15.0-1112.122~20.04.1
linux-azure-fips (Ubuntu package) - addressed in versions 5.15.0.1117.102, 5.15.0-1117.126+fips1
linux-azure-fde (Ubuntu package) - update to 5.15.0-1117.126
linux-ibm (Ubuntu package) - addressed in versions 7.0.0-1008.8, 7.0.0-1010.10
linux-nvidia (Ubuntu package) - addressed in versions 7.0.0-1016.16, 7.0.0-1016.16~24.04.1
linux-nvidia-bos (Ubuntu package) - update to 7.0.0-2016.16
External References
- https://git.kernel.org/stable/c/43cae21424ff8e33894a0f86c6b80b840c049fd7
- https://git.kernel.org/stable/c/6098634cfa711f11a8d65368dc51ec8f7c8241ba
- https://git.kernel.org/stable/c/60c4b9fe1a3dd012014b1f561a6928a0b5db1126
- https://git.kernel.org/stable/c/7896d87cbb05e097efc113243d4e38f9f8cea16c
- https://git.kernel.org/stable/c/83e039f0a43e0708515b0479cb7690fb93faaaa0
- https://git.kernel.org/stable/c/97a9cf2a8217ca1cdaf48cb9ab26e471632c7e7f
- https://git.kernel.org/stable/c/9d5309500b4607b7198e19f0a3fa13eb864cd5fb
- https://git.kernel.org/stable/c/dd47b8c4a0a8ced442da3f008db28fbbd31feaf0
Related Security Bulletins
- Out-of-bounds write in Linux kernel hwmon pmbus driver
- Ubuntu update for linux-nvidia-tegra-5.15
- Ubuntu update for linux
- Ubuntu update for linux-ibm
- Ubuntu update for linux-nvidia-tegra
- Ubuntu update for linux-aws
- Ubuntu update for linux-azure
- Ubuntu update for linux-azure-fde
- Ubuntu update for linux-azure
- Ubuntu update for linux-azure-5.15
- Ubuntu update for linux-aws
- Ubuntu update for linux-azure-fips
- Ubuntu update for linux-intel-iot-realtime
- Ubuntu update for linux-intel-iotg
- Ubuntu update for linux-nvidia-bos
- Ubuntu update for linux-nvidia
- Ubuntu update for linux-gcp-5.15