CVE-2026-64205

Aliases:UBUNTU-CVE-2026-64205DEBIAN-CVE-2026-64205CGA-44w8-fm32-3pvfCGA-hxm4-3hq5-wcwg
Advisory lineage Upstream: 0 Downstream: 9
Analyzed
Published: 20 Jul 2026, 16:27
Last modified:17 Aug 2026, 04:51

Vulnerability Summary

Overall Risk (default)
low
22/100
CVSS Score
5.5 MEDIUM
v3.1 (nvd)
EPSS Score
0.13% LOW
0% probability 0.00%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

20 Jul 2026, 16:27
Published
Vulnerability first disclosed
17 Aug 2026, 04:51
Last Modified
Vulnerability information updated

Description

In the Linux kernel, the following vulnerability has been resolved: i2c: i801: fix hardware state machine corruption in error path A severe livelock and subsequent Hung Task panic were observed in the i2c-i801 driver during concurrent Fuzzing. The crash is caused by an unconditional hardware register cleanup in the error handling path of i801_access(). When i801_check_pre() fails (e.g., returning -EBUSY because the SMBus controller is actively used by BIOS/ACPI), the kernel does not actually acquire the hardware ownership. However, the code jumps to the 'out' label and executes: iowrite8(SMBHSTSTS_INUSE_STS | STATUS_FLAGS, SMBHSTSTS(priv)); This forcefully clears the INUSE_STS lock and resets the hardware status flags without owning the controller. Doing so interrupts ongoing BIOS/ACPI transactions and totally corrupts the SMBus hardware state machine. Consequently, all subsequent i801_access() calls fail at the pre-check stage, triggering an endless stream of "SMBus is busy, can't use it!" error logs. Over a slow serial console, this printk flood monopolizes the CPU (Console Livelock), starving other processes trying to acquire the mmap_lock down_read semaphore, ultimately triggering the hung task watchdog. Fix this by moving the 'out' label below the hardware register cleanup. If i801_check_pre() fails, we safely bypass the iowrite8() and only release the software locks (pm_runtime and mutex), strictly adhering to the rule of not releasing resources that were never acquired.

CVSS Metrics

  • v3.1•MEDIUM•Score: 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS Trends

Current EPSS score: 0.13%• Percentile: 3%

Affected Systems

  • chainguard•linux-gcp-6.18

    < 6.18.44-r0

  • chainguard•linux-gcp-6.18-bootc

    < 6.18.44-r0

  • debian•linux

    < 6.12.101-1 | < 7.1.4-1

  • debian•linux-6.12

    < 6.12.101-1~deb12u1

  • ubuntu•linux

    all | all | < 7.0.0-31.31

  • ubuntu•linux-allwinner-5.19

    all

  • ubuntu•linux-aws

    all | all | < 7.0.0-1012.12

  • ubuntu•linux-aws-5.0

    all

  • ubuntu•linux-aws-5.11

    all

  • ubuntu•linux-aws-5.13

    all

  • ubuntu•linux-aws-5.19

    all

  • ubuntu•linux-aws-5.3

    all

  • ubuntu•linux-aws-5.8

    all

  • ubuntu•linux-aws-6.14

    all

  • ubuntu•linux-aws-6.17

    all

  • ubuntu•linux-aws-6.2

    all

  • ubuntu•linux-aws-6.5

    all

  • ubuntu•linux-aws-6.8

    all

  • ubuntu•linux-aws-7.0

    all | < 7.0.0-1012.12~24.04.1

  • ubuntu•linux-aws-fips

    all

  • ubuntu•linux-azure

    all | all | all

  • ubuntu•linux-azure-5.11

    all

  • ubuntu•linux-azure-5.13

    all

  • ubuntu•linux-azure-5.19

    all

  • ubuntu•linux-azure-5.3

    all

  • ubuntu•linux-azure-5.8

    all

  • ubuntu•linux-azure-6.11

    all

  • ubuntu•linux-azure-6.14

    all

  • ubuntu•linux-azure-6.17

    all

  • ubuntu•linux-azure-6.2

    all

  • ubuntu•linux-azure-6.5

    all

  • ubuntu•linux-azure-6.8

    all

  • ubuntu•linux-azure-7.0

    all

  • ubuntu•linux-azure-edge

    all

  • ubuntu•linux-azure-fde

    all | all | all

  • ubuntu•linux-azure-fde-5.19

    all

  • ubuntu•linux-azure-fde-6.14

    all

  • ubuntu•linux-azure-fde-6.17

    all

  • ubuntu•linux-azure-fde-6.2

    all

  • ubuntu•linux-azure-fde-6.8

    all

  • ubuntu•linux-azure-fde-7.0

    all

  • ubuntu•linux-azure-fips

    all

  • ubuntu•linux-azure-nvidia

    all

  • ubuntu•linux-azure-nvidia-6.14

    all

  • ubuntu•linux-bluefield

    all

  • ubuntu•linux-fips

    all

  • ubuntu•linux-gcp

    all | all | all | < 7.0.0-1011.11

  • ubuntu•linux-gcp-5.11

    all

  • ubuntu•linux-gcp-5.13

    all

  • ubuntu•linux-gcp-5.19

    all

Showing first 50 affected entries in server-rendered view.

References (14)