CVE-2026-98368

Page use-after-free and leak via ESP fragment mutation

Published Oct 6, 2026 · Updated Oct 6, 2026

Memory-safety flaws in Linux kernel ESP output allow context-dependent attackers to trigger page use-after-free and memory leaks via zerocopy packets. On the out-of-place path, ESP changes the fragment array without first clearing managed-fragment ownership: esp_ssg_unref() drops references to ubuf-owned pages, while skb_release_data() skips release of an ESP-owned page. Reachability requires a zerocopy-managed socket buffer to enter that ESP output path; the resulting reference underflow affects pinned pages, and the unreleased page leaks at packet rate.

CVSS severityUnavailable
Unscored
EPSS probability0.13%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Memory-safety flaws in Linux kernel ESP output allow context-dependent attackers to trigger page use-after-free and memory leaks via zerocopy packets. On the out-of-place path, ESP changes the fragment array without first clearing managed-fragment ownership: esp_ssg_unref() drops references to ubuf-owned pages, while skb_release_data() skips release of an ESP-owned page. Reachability requires a zerocopy-managed socket buffer to enter that ESP output path; the resulting reference underflow affects pinned pages, and the unreleased page leaks at packet rate.

The record

CVE
CVE-2026-98368
Published
Oct 6, 2026
Updated
Oct 6, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
Unavailable
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Oct 6, 2026CVE publishedPublication date reported by the CVE source.
  2. Oct 6, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=6.0
  2. Affected versionversion=753f1ca4e1e50248a1b760c9774d6d6b354562cc <0d0845ee61c5df47cc68bc446501f48f71e8dcc6
  3. Affected versionversion=753f1ca4e1e50248a1b760c9774d6d6b354562cc <2359264f377cdbdef2d95868cc8fb572949e48d3
  4. Affected versionversion=753f1ca4e1e50248a1b760c9774d6d6b354562cc <6508304ac2c8cdafca2f4ab915df8c707893e134
  5. Affected versionversion=753f1ca4e1e50248a1b760c9774d6d6b354562cc <69a768c12398cada8528080332c822623fa7064d
  6. Affected versionversion=753f1ca4e1e50248a1b760c9774d6d6b354562cc <6cab554f2c0f28773f712ed3a5479103f42ce844
  7. Affected versionversion=753f1ca4e1e50248a1b760c9774d6d6b354562cc <f89416eb3db151170a6f3c6dfc5239d26cdce4d2

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linuxversion=6.0; version=753f1ca4e1e50248a1b760c9774d6d6b354562cc <0d0845ee61c5df47cc68bc446501f48f71e8dcc6; version=753f1ca4e1e50248a1b760c9774d6d6b354562cc <2359264f377cdbdef2d95868cc8fb572949e48d3; version=753f1ca4e1e50248a1b760c9774d6d6b354562cc <6508304ac2c8cdafca2f4ab915df8c707893e134; version=753f1ca4e1e50248a1b760c9774d6d6b354562cc <69a768c12398cada8528080332c822623fa7064d; version=753f1ca4e1e50248a1b760c9774d6d6b354562cc <6cab554f2c0f28773f712ed3a5479103f42ce844; version=753f1ca4e1e50248a1b760c9774d6d6b354562cc <f89416eb3db151170a6f3c6dfc5239d26cdce4d2

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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