Directory Traversal Affecting runc package, versions <1.0.0~rc7+git20190403.029124da-0ubuntu1~16.04.4+esm2


Severity

Recommended
0.0
high
0
10

Based on Ubuntu security rating.

Threat Intelligence

EPSS
10.25% (96th percentile)

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  • Snyk IDSNYK-UBUNTU1604-RUNC-1629683
  • published19 Aug 2025
  • disclosed27 May 2021

Introduced: 27 May 2021

CVE-2021-30465  (opens in a new tab)
CWE-22  (opens in a new tab)

How to fix?

Upgrade Ubuntu:16.04 runc to version 1.0.0rc7+git20190403.029124da-0ubuntu116.04.4+esm2 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream runc package and not the runc package as distributed by Ubuntu. See How to fix? for Ubuntu:16.04 relevant fixed versions and status.

runc before 1.0.0-rc95 allows a Container Filesystem Breakout via Directory Traversal. To exploit the vulnerability, an attacker must be able to create multiple containers with a fairly specific mount configuration. The problem occurs via a symlink-exchange attack that relies on a race condition.

CVSS Base Scores

version 3.1