CVE-2021-20291
CVE-2021-20291 is a medium-severity vulnerability in Redhat Openshift Container Platform with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-667.
Key facts
- Severity: Medium (CVSS 3.x base score 6.5)
- CVSS v2: 7.1
- EPSS exploit prediction: 2% (73rd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-667
- Affected product: Redhat Openshift Container Platform
- Published:
- Last modified:
Description
A deadlock vulnerability was found in 'github.com/containers/storage' in versions before 1.28.1. When a container image is processed, each layer is unpacked using `tar`. If one of those layers is not a valid `tar` archive this causes an error leading to an unexpected situation where the code indefinitely waits for the tar unpacked stream, which never finishes. An attacker could use this vulnerability to craft a malicious image, which when downloaded and stored by an application using containers/storage, would then cause a deadlock leading to a Denial of Service (DoS).
Frequently asked questions
- What is CVE-2021-20291?
- A deadlock vulnerability was found in 'github.com/containers/storage' in versions before 1.28.1. When a container image is processed, each layer is unpacked using `tar`. If one of those layers is not a valid `tar` archive this causes an error leading to an unexpected situation where the code indefinitely waits for the tar unpacked stream, which never finishes. An attacker could use this vulnerability to craft a malicious image, which when downloaded and stored by an application using containers/storage, would then cause a deadlock leading to a Denial of Service (DoS).
- How severe is CVE-2021-20291?
- CVE-2021-20291 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2021-20291 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-20291?
- CVE-2021-20291 primarily affects Redhat Openshift Container Platform. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-20291?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-20291 published?
- CVE-2021-20291 was published on 2021-04-01 and last updated on 2026-06-17.
References
- https://bugzilla.redhat.com/show_bug.cgi?id=1939485
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/R5D7XL7FL24TWFMGQ3K2S72EOUSLZMKL/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SPYOHNG2Q7DCAQZMGYLMENLKALGDLG3X/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WX24EITRXVHDM5M223BVTJA2ODF2FSHI/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZNMB7O2UIXE34PGSCSOULGHPX5LIJBMM/
- https://unit42.paloaltonetworks.com/cve-2021-20291/
Affected products (5)
- cpe:2.3:a:storage_project:storage:*:*:*:*:*:*:*:*
- cpe:2.3:a:redhat:openshift_container_platform:4.0:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
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