CVE-2026-98417

Received Received - Intake

ESP-in-TCP Transport Header Handling Flaw in Linux Kernel

Publication date: 2026-10-14

Last updated on: 2026-10-19

Assigner: kernel.org

Description

In the Linux kernel, the following vulnerability has been resolved: net: xfrm: reject unrepresentable espintcp transport headers ESP-in-TCP can hand xfrm packets whose transport header offset no longer fits after the stream parser trims the TCP envelope. The plain transport header reset truncates that offset and triggers the skb warning path. Use the careful transport-header helper and drop the skb through the existing XFRM error path when the offset cannot be represented.

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-10-14

Last Modified

2026-10-19

Generated

2026-10-19

AI Q&A

2026-10-15

EPSS Evaluated

2026-10-18

NVD

CVE-2026-98417

EUVD

EUVD-2026-101066

Affected Vendors & Products

Vendor	Product	Version / Range
Linux	Linux	e27cca96cd68fa2c6814c90f9a1cfd36bb68c593
Linux	Linux	e27cca96cd68fa2c6814c90f9a1cfd36bb68c593
Linux	Linux	e27cca96cd68fa2c6814c90f9a1cfd36bb68c593
Linux	Linux	e27cca96cd68fa2c6814c90f9a1cfd36bb68c593
Linux	Linux	e27cca96cd68fa2c6814c90f9a1cfd36bb68c593
Linux	Linux	e27cca96cd68fa2c6814c90f9a1cfd36bb68c593
Linux	Linux	e27cca96cd68fa2c6814c90f9a1cfd36bb68c593
Linux	Linux	e27cca96cd68fa2c6814c90f9a1cfd36bb68c593
Linux	Linux	5.6

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-UNKNOWN

Attack-Flow Graph

Executive Summary

This vulnerability in the Linux kernel involves ESP-in-TCP packets where the transport header offset becomes unrepresentable after the TCP envelope is trimmed. The kernel's handling of these packets triggers a warning due to an invalid transport header reset, which could lead to unexpected behavior or crashes.

Detection Guidance

This vulnerability involves ESP-in-TCP packets with unrepresentable transport headers in the Linux kernel. Detection requires monitoring kernel logs for skb warnings related to transport header offsets. Check for messages like 'skbuff: skb_under_panic' or 'invalid transport header' in dmesg or syslog. Use 'dmesg | grep -i skb' or 'journalctl -k | grep -i transport' to search for related errors.

Impact Analysis

If exploited, this vulnerability could cause system instability, crashes, or denial-of-service conditions in systems running vulnerable Linux kernel versions. It primarily affects network processing involving ESP-in-TCP, potentially disrupting secure communications.

Compliance Impact

This vulnerability affects compliance with standards like GDPR and HIPAA by potentially exposing sensitive network traffic data. The issue involves incorrect handling of ESP-in-TCP packets, which could lead to information disclosure or integrity violations in encrypted communications. Such failures may violate requirements for secure data transmission and protection of personal or health information.

Mitigation Strategies

Update the Linux kernel to the latest patched version to resolve this vulnerability.

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