---
id: CVE-2026-64317
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  isofs: bound Rock Ridge symlink components to the SL record

  get_symlink_chunk() and the SL handling in
  parse_rock_ridge_inode_internal() walk the variable-length compo…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  isofs: bound Rock Ridge symlink components to the SL record

  get_symlink_chunk() and the SL handling in
  parse_rock_ridge_inode_internal() walk the variable-length compo…
severity: high
cvss: 7.1
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H'
cwe:
  - CWE-125
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 2.6.12.1, < 5.10.261'
  - 'linux_kernel >= 5.11, < 5.15.212'
  - 'linux_kernel >= 5.16, < 6.1.178'
  - 'linux_kernel >= 6.2, < 6.6.145'
  - 'linux_kernel >= 6.7, < 6.12.96'
  - 'linux_kernel >= 6.13, < 6.18.39'
  - 'linux_kernel >= 6.19, < 7.1.4'
  - linux_kernel = 2.6.12
patched:
  - linux_kernel 7.1.4
published: '2026-07-25'
updated: '2026-09-08'
sourceUpdated: '2026-09-08T09:18:18.020'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-64317'
references:
  - url: 'https://git.kernel.org/stable/c/1015e1c4b2fadd9c09704e24738e46598778c869'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/36fe7d25dbc40da0c6b1dd4513a4f69ac6164eee'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/5fa1d6a5ec2356d2107dead614437c66fa7138b1'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/6bf41db09ef935d76fcc84ccf213b42c18de95ee'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/9830725078c8483c6831ec10222ae724806ea36b'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/a22cb6bb54dc167047ea9e70d97dfbc2c15649e3'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/b5699642640d6cff357638738c5293985cd5a53d'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/b736b12108fd116c41777628f5a333791604df26'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-019113.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
  - cve.org
epss: 0.00167
epssPercentile: 0.05286
ingestedAt: '2026-07-27T06:16:50.426Z'
---

## Overview

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

isofs: bound Rock Ridge symlink components to the SL record

get_symlink_chunk() and the SL handling in
parse_rock_ridge_inode_internal() walk the variable-length components of
a Rock Ridge "SL" (symbolic link) record.  Each component is a two-byte
header (flags, len) followed by len bytes of text, so it occupies
slp->len + 2 bytes.  Both loops read slp->len and advance to the next
component, and get_symlink_chunk() additionally does
memcpy(rpnt, slp->text, slp->len), but neither checks that the component
lies within the SL record before dereferencing it.

A crafted SL record whose component declares a len that runs past the
record (rr->len) therefore triggers an out-of-bounds read of up to 255
bytes.  When the record sits at the tail of its backing buffer - for
example a small kmalloc()ed continuation block reached through a CE
record - the read crosses the allocation; get_symlink_chunk() then
copies the out-of-bounds bytes into the symlink body returned to user
space by readlink(), disclosing adjacent kernel memory.

ISO 9660 images are routinely mounted from untrusted removable media -
desktop environments auto-mount them (e.g. via udisks2) without
CAP_SYS_ADMIN - so the record contents are attacker-controlled.

Reject any component that does not fit in the remaining record bytes
before using it.  In get_symlink_chunk() return NULL, like the existing
output-buffer (plimit) checks, so a malformed record makes readlink()
fail with -EIO rather than silently returning a truncated target; in
parse_rock_ridge_inode_internal() stop the inode-size walk.

## Affected

- `linux_kernel >= 2.6.12.1, < 5.10.261`
- `linux_kernel >= 5.11, < 5.15.212`
- `linux_kernel >= 5.16, < 6.1.178`
- `linux_kernel >= 6.2, < 6.6.145`
- `linux_kernel >= 6.7, < 6.12.96`
- `linux_kernel >= 6.13, < 6.18.39`
- `linux_kernel >= 6.19, < 7.1.4`
- `linux_kernel = 2.6.12`

## Remediation

Upgrade past the affected range:

- `linux_kernel 7.1.4`