CVE-2026-19730: Podman quadlet install incomplete file truncation

CVE-2026-19730 · Severity: medium · CVSS 4.2 · Published 2026-08-13

Podman's quadlet install command with the --replace flag fails to properly truncate files when replacing Quadlet configuration files. If a new Quadlet is smaller than the original, leftover content from the old file persists, potentially preserving security-sensitive settings like additional capabilities or volume mounts that should have been removed. This could result in unintended container privileges or data exposure when containers are deployed.

Technologies: github.com/containers/podman (Go), github.com/containers/podman/v2 (Go), github.com/containers/podman/v3 (Go), github.com/containers/podman/v4 (Go), github.com/containers/podman/v5 (Go). Vendors: Go.

Quick answers

Is CVE-2026-19730 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-19730 being exploited in the wild.
How severe is CVE-2026-19730?
Medium severity, with a CVSS score of 4.2, published 13 August 2026.
Which products and versions are affected?
github.com/containers/podman (Go) SEMVER:introduced=0; github.com/containers/podman/v2 (Go) SEMVER:introduced=0; github.com/containers/podman/v3 (Go) SEMVER:introduced=0; github.com/containers/podman/v4 (Go) SEMVER:introduced=0; and 1 more.
Is there a fix for CVE-2026-19730?
Yes. github.com/containers/podman/v5 (Go): upgrade to 5.8.6 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-19730 attacked?
It is attacked with local access, in a network appliance.
Am I affected by CVE-2026-19730?
Check whether you run github.com/containers/podman (Go), github.com/containers/podman/v2 (Go), github.com/containers/podman/v3 (Go) or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • github.com/containers/podman/v5 (Go): upgrade to 5.8.6 or later
    go get github.com/containers/podman/v5@v5.8.6

Technical details

The vulnerability is a file truncation failure in podman quadlet install --replace, introduced in podman 5.7.0. When replacing a Quadlet file, if the new file is smaller than the original, the file is not truncated to remove leftover content from the old file. The root cause is improper file handling during replacement. An attacker with access to Quadlet files could exploit this by creating a scenario where security-sensitive configuration lines (such as AddCapability directives or additional Volume mounts) at the end of the original file are retained in the replaced file. The attack requires local access and knowledge of the existing Quadlet structure. The vulnerability has been patched in podman 6.0.0 and 5.8.6.

Affected products

  • Podman Podman 5.7.0 to 5.8.5, 6.0.0-beta and earlier

Identifiers

  • CVE-2026-19730
  • GHSA-fx76-2j3w-2mx6
  • GO-2026-6588

Timeline

  • 2026-09-24: disclosed
  • 2026-09-24: patched: Fixed in podman 6.0.0 and 5.8.6

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