Link following in crun - CVE-2019-18837
Published: November 13, 2019 / Updated: April 27, 2026
Vulnerability identifier: #VU30624
CSH Severity: High
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Amber
CVE-ID: CVE-2019-18837
CWE-ID: CWE-59
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Container Projects
Affected software:
crun
crun
Detailed vulnerability description
The vulnerability allows a remote non-authenticated attacker to gain access to sensitive information.
An issue was discovered in crun before 0.10.5. With a crafted image, it doesn't correctly check whether a target is a symlink, resulting in access to files outside of the container. This occurs in libcrun/linux.c and libcrun/chroot_realpath.c.
How to mitigate CVE-2019-18837
Install update from vendor's website.
Sources
- https://github.com/containers/crun/pull/173
- https://github.com/containers/crun/releases/tag/0.10.5
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/DTA5SJUAKQUK6HRY2CZVJUIZP5BO3EOG/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ITB2UNEGHXZUR3ATYHWPSK5LJB36N7AP/
- https://github.com/containers/crun/security/advisories/GHSA-w969-8gp4-95wr