How severe is CVE-2021-20304?

CVE-2021-20304 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-20304 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (71st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20304?

CVE-2021-20304 affects Openexr. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-20304?

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-2021-20304 published?

CVE-2021-20304 was published on 2022-08-23 and last updated on 2026-06-17.

CVE-2021-20304

CVE-2021-20304 is a high-severity vulnerability in Openexr with a CVSS 3.x base score of 7.5. 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-190.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 2% (71st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-190
Affected product: Openexr
Published: 2022-08-23
Last modified: 2026-06-17

Description

A flaw was found in OpenEXR's hufDecode functionality. This flaw allows an attacker who can pass a crafted file to be processed by OpenEXR, to trigger an undefined right shift error. The highest threat from this vulnerability is to system availability.

Frequently asked questions

What is CVE-2021-20304?: A flaw was found in OpenEXR's hufDecode functionality. This flaw allows an attacker who can pass a crafted file to be processed by OpenEXR, to trigger an undefined right shift error. The highest threat from this vulnerability is to system availability.
How severe is CVE-2021-20304?: CVE-2021-20304 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-20304 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20304?: CVE-2021-20304 affects Openexr. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-20304?: 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-2021-20304 published?: CVE-2021-20304 was published on 2022-08-23 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:openexr:openexr:*:*:*:*:*:*:*:*

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