runc vulnerable to container breakout through process.cwd trickery and leaked fds

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

8.6 · CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

EPSS

• CVE-2024-21626: 18.92% estimated exploitation activity in the next 30 days; percentile 97.30 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Impact In runc 1.1.11 and earlier, due to an internal file descriptor leak, an attacker could cause a newly-spawned container process (from runc exec) to have a working directory in the host filesystem namespace, allowing for a container escape by giving access to the host filesystem ("attack 2"). The same attack could be used by a malicious image to allow a container process to gain access to the host filesystem through runc run ("attack 1"). Variants of attacks 1 and 2 could be also be used to overwrite semi-arbitrary host binaries, allowing for complete container escapes ("attack 3a" and "attack 3b"). Strictly speaking, while attack 3a is the most severe from a CVSS perspective, attacks 2 and 3b are arguably more dangerous in practice because they allow for a breakout from inside a container as opposed to requiring a user execute a malicious image. The reason attacks 1 and 3a are scored higher is because being able to socially engineer users is treated as a given for UI:R vectors,…

Published by the source

31 Jan 2024, 22:44 UTC

Last modified by the source

21 Jul 2026, 14:42 UTC

Source last checked

26 Oct 2026, 15:27 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-xr7r-f8xq-vfvv

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# Patch Next advisory brief: CVE-2024-21626

Advisory: runc vulnerable to container breakout through process.cwd trickery and leaked fds
IDs: CVE-2024-21626, GHSA-xr7r-f8xq-vfvv
Record: https://patchnext.com/advisories/cve-2024-21626 (revision 1, source checked 26 Oct 2026, 15:27 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.6)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/opencontainers/runc 1.1.12. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/opencontainers/runc: affected >= 1.0.0-rc93, <= 1.1.11; fixed in 1.1.12

## Suggested inspection (read-only)
- Go github.com/opencontainers/runc: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/opencontainers/runc.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-xr7r-f8xq-vfvv (GitHub-reviewed advisory GHSA-xr7r-f8xq-vfvv lists affected ranges: Go github.com/opencontainers/runc >=1.0.0-rc93 <=1.1.11)

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