How severe is CVE-2021-45977?

CVE-2021-45977 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-45977 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-45977?

CVE-2021-45977 primarily affects Jetbrains Clion. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-45977?

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

When was CVE-2021-45977 published?

CVE-2021-45977 was published on 2022-02-25 and last updated on 2026-06-17.

CVE-2021-45977

CVE-2021-45977 is a critical-severity vulnerability in Jetbrains Clion with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 1% (61st percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Jetbrains Clion
Published: 2022-02-25
Last modified: 2026-06-17

Description

JetBrains IntelliJ IDEA 2021.3.1 Preview, IntelliJ IDEA 2021.3.1 RC, PyCharm Professional 2021.3.1 RC, GoLand 2021.3.1, PhpStorm 2021.3.1 Preview, PhpStorm 2021.3.1 RC, RubyMine 2021.3.1 Preview, RubyMine 2021.3.1 RC, CLion 2021.3.1, WebStorm 2021.3.1 Preview, and WebStorm 2021.3.1 RC (used as Remote Development backend IDEs) bind to the 0.0.0.0 IP address. The fixed versions are: IntelliJ IDEA 2021.3.1, PyCharm Professional 2021.3.1, GoLand 2021.3.2, PhpStorm 2021.3.1 (213.6461.83), RubyMine 2021.3.1, CLion 2021.3.2, and WebStorm 2021.3.1.

Frequently asked questions

What is CVE-2021-45977?: JetBrains IntelliJ IDEA 2021.3.1 Preview, IntelliJ IDEA 2021.3.1 RC, PyCharm Professional 2021.3.1 RC, GoLand 2021.3.1, PhpStorm 2021.3.1 Preview, PhpStorm 2021.3.1 RC, RubyMine 2021.3.1 Preview, RubyMine 2021.3.1 RC, CLion 2021.3.1, WebStorm 2021.3.1 Preview, and WebStorm 2021.3.1 RC (used as Remote Development backend IDEs) bind to the 0.0.0.0 IP address. The fixed versions are: IntelliJ IDEA 2021.3.1, PyCharm Professional 2021.3.1, GoLand 2021.3.2, PhpStorm 2021.3.1 (213.6461.83), RubyMine 2021.3.1, CLion 2021.3.2, and WebStorm 2021.3.1.
How severe is CVE-2021-45977?: CVE-2021-45977 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-45977 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-45977?: CVE-2021-45977 primarily affects Jetbrains Clion. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-45977?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-45977 published?: CVE-2021-45977 was published on 2022-02-25 and last updated on 2026-06-17.

References

Affected products (11)

cpe:2.3:a:jetbrains:clion:2021.3.1:*:*:*:*:*:*:*
cpe:2.3:a:jetbrains:goland:2021.3.1:*:*:*:*:*:*:*
cpe:2.3:a:jetbrains:intellij_idea:2021.3.1:preview:*:*:*:*:*:*
cpe:2.3:a:jetbrains:intellij_idea:2021.3.1:rc:*:*:*:*:*:*
cpe:2.3:a:jetbrains:phpstorm:2021.3.1:preview:*:*:*:*:*:*
cpe:2.3:a:jetbrains:phpstorm:2021.3.1:rc:*:*:*:*:*:*
cpe:2.3:a:jetbrains:pycharm:2021.3.1:2021.3.1:*:*:professional:*:*:*
cpe:2.3:a:jetbrains:rubymine:2021.3.1:preview:*:*:*:*:*:*
cpe:2.3:a:jetbrains:rubymine:2021.3.1:rc:*:*:*:*:*:*
cpe:2.3:a:jetbrains:webstorm:2021.3.1:preview:*:*:*:*:*:*
cpe:2.3:a:jetbrains:webstorm:2021.3.1:rc:*:*:*:*:*:*

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