CRITICAL: CVE-2026-53363 (CVSS 9.8) — multiple products

CVE: CVE-2026-53363

CVSS: 9.8 (3.1) — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Severity: CRITICAL

Status: Critical advisory

Affected

_See vendor advisory_

Summary

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

xfrm: iptfs: preserve shared-frag marker in iptfs_consume_frags()

iptfs_consume_frags() transfers paged fragments from one socket buffer

to another but fails to propagate the SKBFL_SHARED_FRAG flag. This is

the same class of bug that was fixed in skb_try_coalesce() for

CVE-2026-46300: when fragments backed by read-only page-cache pages are

merged, the marker indicating their shared nature must be preserved so

that ESP can decide correctly whether in-place encryption is safe.

Apply the same two-line fix used in skb_try_coalesce() to

iptfs_consume_frags().

Verified Sources

• NVD entry
• GitHub Advisory
• MITRE

References

• https://git.kernel.org/stable/c/c885d111ed9f5a0a1f3cc4e87a50db6518abaa6c
• https://git.kernel.org/stable/c/dd66f7f6e360ee82cd905517726f8e9091265de5
• https://git.kernel.org/stable/c/e9096a5a170e7ecd6467bc2e08668ec39897cda7

_Validated by the Lyrie Threat Intelligence Pipeline — 3 independent sources confirmed before publication. No speculation._