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Vulnerability record · public intelligence
CVE-2019-19921
UNKNOWN

opencontainers runc contains procfs race condition with a shared volume mount

Published Feb 12, 2020 · Updated Nov 3, 2026

Severity · CVSSUNKNOWN · Not scored
Known exploitationNot listed
EPSS / likelihood0.43%
QFinch risk scoreNot available

Original summary

Normalized public record · Updated Nov 3, 2026

opencontainers runc contains procfs race condition with a shared volume mount

Publisher and source text is retained separately from QFinch interpretation.

QFinch assessment

By crafting a malicious root filesystem (with `/proc` being a symlink to a directory which was inside a volume shared with another running container), an attacker in control of both containers can trick `runc` into not correctly configuring the container's security labels and not correctly masking paths inside `/proc` which contain potentially-sensitive information about the host (or even allow for direct attacks against the host).

Potential impact

By crafting a malicious root filesystem (with /proc being a symlink to a directory which was inside a volume shared with another running container), an attacker in control of both containers can trick runc into not correctly configuring the container's security labels and not correctly masking paths inside /proc which contain potentially-sensitive information about the host (or even allow for direct attacks against the host). In order to exploit this bug, an untrusted user must be able to spawn custom containers with custom mount configurations (such that a volume is shared between two containers). It should be noted that we consider this to be a fairly high level of access for an untrusted user -- and we do not recommend allowing completely untrusted users to have such degrees of access without further restrictions.

Evidence: public source records

Affected products

Affected scope reported by the available public evidence
Affected package, product or rangeFix status
Consult the referenced vendor advisory for affected versions.Consult source advisory

Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.

Remediation

Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.

  1. Confirm the affected product and reachable code path exist in your environment.
  2. Apply the vendor-supported patch or mitigation from the primary advisory.
  3. Rescan the exact deployed revision and retain verification evidence.
Review primary references

Evidence coverage

FIRST-EPSSCVE-LIST-V5
SSVC priority
MEDIUM
Confidence
Not available
Aliases
None reported

Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.

Sources and record history

  1. GitHub advisory ↗
  2. security-tracker.debian.org ↗
  3. Source repository ↗
  4. Source repository ↗
  5. openSUSE-SU-2020:0219 ↗
  6. RHSA-2020:0688 ↗
  7. RHSA-2020:0695 ↗
  8. GLSA-202003-21 ↗
  9. USN-4297-1 ↗
  10. [debian-lts-announce] 20230327 [SECURITY] [DLA 3369-1] runc security update ↗
  11. FEDORA-2023-1bcbb1db39 ↗
  12. FEDORA-2023-3cccbc4c95 ↗

Record history

Published Feb 12, 2020 · Last refreshed Nov 3, 2026

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