Incorrect Calculation of Buffer Size Affecting linux-qemu-6.18 package, versions <6.18.31-r0


Severity

Recommended
0.0
medium
0
10

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Threat Intelligence

EPSS
0.16% (5th percentile)

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  • Snyk IDSNYK-CHAINGUARDLATEST-LINUXQEMU618-16743290
  • published18 May 2026
  • disclosed6 May 2026

Introduced: 6 May 2026

CVE-2026-43107  (opens in a new tab)
CWE-131  (opens in a new tab)

How to fix?

Upgrade Chainguard linux-qemu-6.18 to version 6.18.31-r0 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream linux-qemu-6.18 package and not the linux-qemu-6.18 package as distributed by Chainguard. See How to fix? for Chainguard relevant fixed versions and status.

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

xfrm: account XFRMA_IF_ID in aevent size calculation

xfrm_get_ae() allocates the reply skb with xfrm_aevent_msgsize(), then build_aevent() appends attributes including XFRMA_IF_ID when x->if_id is set.

xfrm_aevent_msgsize() does not include space for XFRMA_IF_ID. For states with if_id, build_aevent() can fail with -EMSGSIZE and hit BUG_ON(err < 0) in xfrm_get_ae(), turning a malformed netlink interaction into a kernel panic.

Account XFRMA_IF_ID in the size calculation unconditionally and replace the BUG_ON with normal error unwinding.

CVSS Base Scores

version 3.1