🛡️ CVE-2025-40189 — kernel

⚪ Unknown ✅ No Known Exploit NVD
N/A
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

net: usb: lan78xx: Fix lost EEPROM read timeout error(-ETIMEDOUT) in lan78xx_read_raw_eeprom

In the Linux kernel, the following vulnerability has been resolved:

net: usb: lan78xx: Fix lost EEPROM read timeout error(-ETIMEDOUT) in lan78xx_read_raw_eeprom

Syzbot reported read of uninitialized variable BUG with following call stack.

lan78xx 8-1:1.0 (unnamed net_device) (uninitialized): EEPROM read operation timeout

=====================================================

BUG: KMSAN: uninit-value in lan78xx_read_eeprom drivers/net/usb/lan78xx.c:1095 [inline]

BUG: KMSAN: uninit-value in lan78xx_init_mac_address drivers/net/usb/lan78xx.c:1937 [inline]

BUG: KMSAN: uninit-value in lan78xx_reset+0x999/0x2cd0 drivers/net/usb/lan78xx.c:3241

lan78xx_read_eeprom drivers/net/usb/lan78xx.c:1095 [inline]

lan78xx_init_mac_address drivers/net/usb/lan78xx.c:1937 [inline]

lan78xx_reset+0x999/0x2cd0 drivers/net/usb/lan78xx.c:3241

lan78xx_bind+0x711/0x1690 drivers/net/usb/lan78xx.c:3766

lan78xx_probe+0x225c/0x3310 drivers/net/usb/lan78xx.c:4707

Local variable sig.i.i created at:

lan78xx_read_eeprom drivers/net/usb/lan78xx.c:1092 [inline]

lan78xx_init_mac_address drivers/net/usb/lan78xx.c:1937 [inline]

lan78xx_reset+0x77e/0x2cd0 drivers/net/usb/lan78xx.c:3241

lan78xx_bind+0x711/0x1690 drivers/net/usb/lan78xx.c:3766

The function lan78xx_read_raw_eeprom failed to properly propagate EEPROM

read timeout errors (-ETIMEDOUT). In the fallthrough path, it first

attempted to restore the pin configuration for LED outputs and then

returned only the status of that restore operation, discarding the

original timeout error.

As a result, callers could mistakenly treat the data buffer as valid

even though the EEPROM read had actually timed out with no data or partial

data.

To fix this, handle errors in restoring the LED pin configuration separately.

If the restore succeeds, return any prior EEPROM timeout error correctly

to the caller.

Affected software

CVE-2025-40189 is recorded against 2 packages.

  • kernel (from 6.14.0 up to 6.17.4)
  • unknown

Timeline and source

Published on 12 November 2025 and last revised on 15 July 2026. No public exploit is currently recorded for this entry. Record sourced from NVD.

References

git.kernel.org (Web)
git.kernel.org (Web)
github.com (Advisory)
nvd.nist.gov (Advisory)
git.kernel.org (Package)

CVE-2025-40189 on other distributions

Each distribution ships its own build and its own fixed version. Pick the one you run:

Details

Severity Unknown
CVSS Score N/A
CVSS Vector N/A
CWE N/A
Public Exploit ✅ No
Source NVD
Published 2025-11-12
Updated 2026-08-12
Modified 2026-07-15
Fix URL N/A

Affected Packages

Software From version Fixed in
kernel 6.14.0 6.17.4
unknown — —

Similar Threats

Free Vulnerability Check

Is your site affected by CVE-2025-40189?

BotEraser helps you identify potentially vulnerable plugins and themes by checking your installation against CVE-2025-40189 and other known CVE records.

Scan My Site Free →

No credit card required  ·  Results in minutes

ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.