Summary
runc can be confused to create empty files/directories on the host
Workarounds
Using user namespaces restricts this attack fairly significantly such that the
attacker can only create inodes in directories that the remapped root
user/group has write access to. Unless the root user is remapped to an actual
user on the host (such as with rootless containers that don't use
/etc/sub[ug]id), this in practice means that an attacker would only be able to
create inodes in world-writable directories.
A strict enough SELinux or AppArmor policy could in principle also restrict the
scope if a specific label is applied to the runc runtime, though we haven't
thoroughly tested to what extent the standard existing policies block this
attack nor what exact policies are needed to sufficiently restrict this attack.
Credits
Thanks to Rodrigo Campos Catelin (@rata) and Alban Crequy (@alban) from
Microsoft for discovering and reporting this vulnerability.
Impact
runc 1.1.13 and earlier as well as 1.2.0-rc2 and earlier can be tricked into
creating empty files or directories in arbitrary locations in the host
filesystem by sharing a volume between two containers and exploiting a race
with os.MkdirAll. While this can be used to create empty files, existing
files will not be truncated.
An attacker must have the ability to start containers using some kind of custom
volume configuration. Containers using user namespaces are still affected, but
the scope of places an attacker can create inodes can be significantly reduced.
Sufficiently strict LSM policies (SELinux/Apparmor) can also in principle block
this attack -- we suspect the industry standard SELinux policy may restrict
this attack's scope but the exact scope of protection hasn't been analysed.
This is exploitable using runc directly as well as through Docker and
Kubernetes.
The CVSS score for this vulnerability is
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N (Low severity, 3.6).
CVE-2024-45310 has a CVSS score of 3.6 (Medium). The vector is requires local access, no privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (1.1.14, 1.2.0-rc.3); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Already deployed Kodem?
See it in your environmentNew to Kodem? Get a demo →Remediation advice
Fixed in runc v1.1.14 and v1.2.0-rc3.
mainpatches:release-1.1patches:
Frequently Asked Questions
- What is CVE-2024-45310? CVE-2024-45310 is a medium-severity security vulnerability in github.com/opencontainers/runc (go), affecting versions < 1.1.14. It is fixed in 1.1.14, 1.2.0-rc.3.
- How severe is CVE-2024-45310? CVE-2024-45310 has a CVSS score of 3.6 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of github.com/opencontainers/runc are affected by CVE-2024-45310? github.com/opencontainers/runc (go) versions < 1.1.14 is affected.
- Is there a fix for CVE-2024-45310? Yes. CVE-2024-45310 is fixed in 1.1.14, 1.2.0-rc.3. Upgrade to this version or later.
- Is CVE-2024-45310 exploitable, and should I be worried? Whether CVE-2024-45310 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2024-45310 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2024-45310?
- Upgrade
github.com/opencontainers/runcto 1.1.14 or later - Upgrade
github.com/opencontainers/runcto 1.2.0-rc.3 or later
- Upgrade