Integer Underflow Affecting kernel6.18-headers package, versions <1:6.18.56-125.164.amzn2023


Severity

Recommended
high

Based on Amazon Linux security rating.

Threat Intelligence

EPSS
0.17% (7th percentile)

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  • Snyk IDSNYK-AMZN2023-KERNEL618HEADERS-21803151
  • published29 Oct 2026
  • disclosed18 Oct 2026

Introduced: 18 Oct 2026

NewCVE-2026-98446  (opens in a new tab)
CWE-191  (opens in a new tab)

How to fix?

Upgrade Amazon-Linux:2023 kernel6.18-headers to version 1:6.18.56-125.164.amzn2023 or higher.
This issue was patched in ALAS2023-2026-3251.

NVD Description

Note: Versions mentioned in the description apply only to the upstream kernel6.18-headers package and not the kernel6.18-headers package as distributed by Amazon-Linux. See How to fix? for Amazon-Linux:2023 relevant fixed versions and status.

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

xfs: don't let hidden_space go negative in xfs_metafile_resv_init

LOLLM points out that if the amount of fdblocks that we can reserve for a metadata btree file goes below the space already used by that file, then the hidden_space subtraction can underflow, causing xfs_dec_fdblocks to subtract a huge amount of space. We never want the target to be less than the used sapce, so fix the logic that adjusts dblocks_avail downwards.

Also fix an error in the adjacent comment.

CVSS Base Scores

version 3.1