---
id: CVE-2026-89608
title: 'kernel: ecryptfs: pass packet set buffer size to parser (CVE-2026-89608)'
summary: >-
  A flaw was found in the `ecryptfs` component of the Linux kernel. The
  `ecryptfs_parse_packet_set()` function incorrectly calculates the available
  buffer size when processing version 1 headers, leading to an overstatement of
  the buffer's ac…
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
cvssSource: vendor
cwe: CWE-131
vendor: Red Hat
product: Red Hat Enterprise Linux 6
affected:
  - enterprise_linux 6
published: '2026-09-11'
updated: '2026-09-18'
sourceUpdated: '2026-09-18T19:09:41+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89608.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89608.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-89608'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532240'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-89608'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89608'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89608.mbox
  - url: 'https://git.kernel.org/stable/c/e7573b0e3058c6bbdfe81673f22c09900fde9e65'
  - url: 'https://git.kernel.org/stable/c/66a87559ecb26afe80ad512faf728a158e2b81da'
  - url: 'https://git.kernel.org/stable/c/3bd9bb3e167a7c14a50423f6ff03ee0fb007199d'
  - url: 'https://git.kernel.org/stable/c/749fa08d8f1b318bd8f4669a14a8a4a8c1bbdaac'
  - url: 'https://git.kernel.org/stable/c/329de8b9e988b152b938f09224670d97bada0b96'
  - url: 'https://git.kernel.org/stable/c/e5d254e654f2311a3c4b9c791d7f216554bcd17a'
  - url: 'https://git.kernel.org/stable/c/747fd45be396a6aea3420ab657a0ab4e60185b05'
  - url: 'https://git.kernel.org/stable/c/2602b79c5b3e2f6fce12e38a670f8e3fda4e46a2'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
epss: 0.00159
epssPercentile: 0.05527
scores:
  vendor: 5.5
  cna: 7.1
ingestedAt: '2026-09-14T15:23:07.450Z'
---

## Overview

A flaw was found in the `ecryptfs` component of the Linux kernel. The `ecryptfs_parse_packet_set()` function incorrectly calculates the available buffer size when processing version 1 headers, leading to an overstatement of the buffer's actual capacity. This miscalculation could allow an attacker to cause a denial of service or potentially lead to information disclosure due to out-of-bounds memory access.

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 6 · no fix planned: Red Hat Enterprise Linux 6 · updated 2026-09-18 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89608.json)

**kernel: ecryptfs: pass packet set buffer size to parser** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-18.

Affected:

- Red Hat Enterprise Linux 6

No fix planned:

- Red Hat Enterprise Linux 6

Not affected:

- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat OpenShift Container Platform 4

## Remediation

Out of support scope