CVE-2021-3602: An information disclosure flaw was found in Buildah, when building containers using chroot isolation

Routine

MEDIUM 5.5WATCHLISTUPGRADEMITIGATEMITIGATE

CVE-2021-3602 is a medium-severity flaw (CVSS 5.5) affecting buildah, enterprise linux, enterprise linux for ibm z systems. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

An information disclosure flaw was found in Buildah, when building containers using chroot isolation. Running processes in container builds (e.g. Dockerfile RUN commands) can access environment variables from parent and grandparent processes. When run in a container in a CI/CD environment, environment variables may include sensitive information that was shared with the container in order to be used only by Buildah itself (e.g. container registry

Why this priority

On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score	5.5 (Medium)
Attack vector	Local
Attack complexity	Low
Privileges needed	Low
User interaction	None
EPSS exploit chance	0.3% (top 74%)
CISA exploited list	No
Weakness	CWE-200, CWE-212
Published	2022-03-03
Last modified	2026-06-17

Publisher (CNA): Red Hat, Inc. · Vendor: buildah project · redhat

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2022-03-03 19:15 UTCPublished CVE record published
2026-06-17 04:05 UTCUpdated Record last modified

buildah project buildah UPGRADE

Affected: < 1.16.8 · >= 1.17.0 and < 1.17.2 · >= 1.19.0 and < 1.19.9 · >= 1.21.0 and < 1.21.3

Fixed in: 1.16.8, 1.17.2, 1.19.9, 1.21.3

Safe to downgrade to: a release before 1.17.0

1. Check installed version

apt-cache policy buildah || rpm -q buildah || buildah --version

2. UPGRADE to 1.16.8 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade buildah

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade buildah

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 1.17.0 (Debian / Ubuntu)

apt-cache madison buildah sudo apt install buildah=<VERSION_BEFORE_1.17.0> sudo apt-mark hold buildah

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list buildah sudo dnf downgrade buildah-<VERSION_BEFORE_1.17.0> sudo dnf versionlock add buildah

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

redhat enterprise linux MITIGATE

Affected: 8.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 8.0

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

redhat enterprise linux for ibm z systems MITIGATE

Affected: 8.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 8.0

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

redhat enterprise linux for power little endian MITIGATE

Affected: 8.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 8.0

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2021-3602?

buildah: upgrade to 1.16.8, 1.17.2, 1.19.9, 1.21.3; enterprise linux: mitigate or apply the listed mitigation; enterprise linux for ibm z systems: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2021-3602 being exploited?

CVE-2021-3602 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2021-3602 affect?

CVE-2021-3602 affects buildah, enterprise linux, enterprise linux for ibm z systems. Severity is medium (CVSS 5.5). An information disclosure flaw was found in Buildah, when building containers using chroot isolation. Running processes in container builds (e.g. Dockerfile RUN commands) can access environment variables from parent and grandparent processe

How urgent is CVE-2021-3602?

Priority 31/100. On your watchlist

Related CVEs

CVE-2024-9675 HIGH 7.8 MITIGATE DOWNGRADE A vulnerability was found in Buildah
CVE-2022-2990 HIGH 7.1 UPGRADE DOWNGRADE An incorrect handling of the supplementary groups in the Buildah container engine might lead to the sensitive
CVE-2022-27651 MEDIUM 6.8 UPGRADE MITIGATE A flaw was found in buildah where containers were incorrectly started with non-empty default permissions
CVE-2020-10696 HIGH 8.8 UPGRADE DOWNGRADE A path traversal flaw was found in Buildah in versions before 1.14.5
CVE-2019-10214 MEDIUM 5.9 MITIGATE MITIGATE The containers/image library used by the container tools Podman, Buildah, and Skopeo in Red Hat Enterprise Lin

References

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