Review reviewCritical

CVE-2026-53363

Linux Linux, linux kernel

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_coale...

CVSS
9.8
EPSS
0.29%
21.8% percentile
CISA KEV
Not listed
Published
2026.07.10
PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability0.29%
Technical severityCVSS 9.8

Vulnerability overview

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_coale...

Affected product and versions

Product
Linux Linux, linux kernel
Affected versions
>= b96ba312e21c9b7ac1526829b9640ddc06695c0b < dd66f7f6e360ee82cd905517726f8e9091265de5, >= b96ba312e21c9b7ac1526829b9640ddc06695c0b < c885d111ed9f5a0a1f3cc4e87a50db6518abaa6c, >= b96ba312e21c9b7ac1526829b9640ddc06695c0b < e9096a5a170e7ecd6467bc2e08668ec39897cda7, >= 6.14, >= 6.14 < 6.18.36, >= 6.19 < 7.0.13, 7.1
Fixed versions
6.18.36, 7.0.13

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that Linux Linux, linux kernel and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE
Not available