CVE-2026-45865

mctp i2c: initialise event handler read bytes

MEDIUM

5.5

CVSS Score

Published: May 27, 2026 at 12:15 PM UTC

Updated: June 27, 2026 at 11:41 AM UTC

1 product affected across 1 vendorLinux Kernel

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Severity

MEDIUM5.5

Exploit prediction

EPSS 0.2%

Description

In the Linux kernel, the following vulnerability has been resolved: mctp i2c: initialise event handler read bytes Set a 0xff value for i2c reads of an mctp-i2c device. Otherwise reads will return "val" from the i2c bus driver. For i2c-aspeed and i2c-npcm7xx that is a stack uninitialised u8. Tested with "i2ctransfer -y 1 r10@0x34" where 0x34 is a mctp-i2c instance, now it returns all 0xff.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Linux Kernel · Linux

95%

5.18 ≤ v < 6.1.1655.18 ≤ v < 6.12.755.18 ≤ v < 6.18.145.18 ≤ v < 6.19.45.18 ≤ v < 6.6.1285.18 ≤ v < 7.06.13 ≤ v < 6.18.146.19 ≤ v < 6.19.46.2 ≤ v < 6.6.1286.7 ≤ v < 6.12.755.18f5b8abf9fc3dacd7529d363e26fe8230935d65f8

Vendor states this is fixed in 11f83253244060b5de5eac787f61ae3f3e559d01 (fixed)

Vendor states this is fixed in 1eeedb310229bfee9dd4d992e5bba33fe1378a8f (fixed)

Vendor states this is fixed in 2a14e91b6d76639dac70ea170f4384c1ee3cb48d (fixed)

Vendor states this is fixed in 6ff2ebfef75fbc57d937d8fbe738b967edf2d331 (fixed)

Vendor states this is fixed in 93e01e837e105299f1c259ef71f6e1ec4fe806e3 (fixed)

Vendor states this is fixed in fa9861e5c8af7651dddfa8d490aaada17ae33b6c (fixed)

Vendor states this is fixed in 5.18 (unaffected)

Vendor states this is fixed in 6.1.165 (unaffected)

Vendor states this is fixed in 6.12.75 (unaffected)

Vendor states this is fixed in 6.18.14 (unaffected)

Vendor states this is fixed in 6.19.4 (unaffected)

Vendor states this is fixed in 6.6.128 (unaffected)