Vulnerability · Published Aug 14, 2026 · Assigned by GitHub_M

CVE-2026-47766crun follows rootfs /dev symlink while creating default devices

Medium 5.1

In plain English

A medium-severity security flaw in crun from containers. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 9% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 4.0)5.1Medium
Exploit odds (30 days)0.2%top 90.7% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

crun is an open source OCI Container Runtime fully written in C. Prior to version 1.28, crun's default device setup opens the container rootfs `/dev` directory without `O_NOFOLLOW`. If an OCI bundle contains `rootfs/dev` as a symlink and the bundle configuration does not mount `/dev`, crun follows that symlink and creates the default device nodes and stdio symlinks at the symlink target outside the container rootfs. In a local rootful crun replay, this created fixed device nodes and symlinks outside the rootfs before crun returned failure. A pre-existing file named `ptmx` in the target directory was also replaced by crun's forced `ptmx -> pts/ptmx` symlink. Version 1.28 fixes the issue.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Alpine:v3.23crun1.28-r0ALPINE-CVE-2026-47766
Alpine:v3.24crun1.28-r0ALPINE-CVE-2026-47766
Debian:12crunno fix listedDEBIAN-CVE-2026-47766
Debian:13crunno fix listedDEBIAN-CVE-2026-47766
Debian:14crun1.28-1DEBIAN-CVE-2026-47766
Ubuntu:22.04:LTScrunno fix listedUBUNTU-CVE-2026-47766
Ubuntu:24.04:LTScrunno fix listedUBUNTU-CVE-2026-47766
Ubuntu:25.10crunno fix listedUBUNTU-CVE-2026-47766
Ubuntu:26.04:LTScrunno fix listedUBUNTU-CVE-2026-47766
Ubuntu:26.10crunno fix listedUBUNTU-CVE-2026-47766

Affected products (as reported)

VendorProductVersions
containers crun < 1.28

Weakness: CWE-61 · Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

References