How severe is CVE-2021-30504?

CVE-2021-30504 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-2021-30504 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-30504?

CVE-2021-30504 affects Jetbrains Intellij Idea. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-30504?

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-2021-30504 published?

CVE-2021-30504 was published on 2021-05-11 and last updated on 2026-06-17.

CVE-2021-30504

CVE-2021-30504 is a high-severity vulnerability in Jetbrains Intellij Idea 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-400.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (81st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-400
Affected product: Jetbrains Intellij Idea
Published: 2021-05-11
Last modified: 2026-06-17

Description

In JetBrains IntelliJ IDEA before 2021.1, DoS was possible because of unbounded resource allocation.

Frequently asked questions

What is CVE-2021-30504?: In JetBrains IntelliJ IDEA before 2021.1, DoS was possible because of unbounded resource allocation.
How severe is CVE-2021-30504?: CVE-2021-30504 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-2021-30504 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-30504?: CVE-2021-30504 affects Jetbrains Intellij Idea. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-30504?: 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-2021-30504 published?: CVE-2021-30504 was published on 2021-05-11 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:jetbrains:intellij_idea:*:*:*:*:*:*:*:*

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