How severe is CVE-2021-33183?

CVE-2021-33183 has a CVSS 3.x base score of 7.9, rated high severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2021-33183 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-33183?

CVE-2021-33183 affects Synology Docker. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-33183?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-33183 published?

CVE-2021-33183 was published on 2021-06-01 and last updated on 2026-06-17.

CVE-2021-33183

CVE-2021-33183 is a high-severity vulnerability in Synology Docker with a CVSS 3.x base score of 7.9. 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-22.

Key facts

Severity: High (CVSS 3.x base score 7.9)
CVSS v2: 3.6
EPSS exploit prediction: 0% (20th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-22
Affected product: Synology Docker
Published: 2021-06-01
Last modified: 2026-06-17

Description

Improper limitation of a pathname to a restricted directory ('Path Traversal') vulnerability container volume management component in Synology Docker before 18.09.0-0515 allows local users to read or write arbitrary files via unspecified vectors.

Frequently asked questions

What is CVE-2021-33183?: Improper limitation of a pathname to a restricted directory ('Path Traversal') vulnerability container volume management component in Synology Docker before 18.09.0-0515 allows local users to read or write arbitrary files via unspecified vectors.
How severe is CVE-2021-33183?: CVE-2021-33183 has a CVSS 3.x base score of 7.9, rated high severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2021-33183 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33183?: CVE-2021-33183 affects Synology Docker. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-33183?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-33183 published?: CVE-2021-33183 was published on 2021-06-01 and last updated on 2026-06-17.

References

https://www.synology.com/security/advisory/Synology_SA_21_08

Affected products (1)

cpe:2.3:a:synology:docker:*:*:*:*:*:*:*:*

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