CVE-2026-89557 Linux Kernel - Integer Overflow

Linux kernel contains an integer overflow caused by lack of overflow check on sb->bblog_shift in super_1_load(), letting attackers trigger overflow in badblocks_set() via crafted superblock, exploit requires crafted on-disk superblock.

CVSS base score 7.8 /10
High
CISA KEV
Not listed
Public exploit
None known
EPSS
0.17% chance of exploitation in 30 days
View the NVD record ↗

Details

Type
Integer Overflow
Impact
Denial Of Service
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Published
11 September 2026
Updated
15 October 2026

Vendor fix

Update to the latest Linux kernel version with the overflow check in super_1_load()

Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them.

References

← All CVEs