How severe is CVE-2021-33591?

CVE-2021-33591 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-33591 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-2021-33591?

CVE-2021-33591 affects Naver Comic Viewer. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-33591?

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-2021-33591 published?

CVE-2021-33591 was published on 2021-05-28 and last updated on 2026-06-17.

CVE-2021-33591

CVE-2021-33591 is a high-severity vulnerability in Naver Comic Viewer with a CVSS 3.x base score of 8.8. 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-489.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.8
EPSS exploit prediction: 2% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-489
Affected product: Naver Comic Viewer
Published: 2021-05-28
Last modified: 2026-06-17

Description

An exposed remote debugging port in Naver Comic Viewer prior to 1.0.15.0 allowed a remote attacker to execute arbitrary code via a crafted HTML page.

Frequently asked questions

What is CVE-2021-33591?: An exposed remote debugging port in Naver Comic Viewer prior to 1.0.15.0 allowed a remote attacker to execute arbitrary code via a crafted HTML page.
How severe is CVE-2021-33591?: CVE-2021-33591 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-33591 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-2021-33591?: CVE-2021-33591 affects Naver Comic Viewer. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-33591?: 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-2021-33591 published?: CVE-2021-33591 was published on 2021-05-28 and last updated on 2026-06-17.

References

https://cve.naver.com/detail/cve-2021-33591

Affected products (1)

cpe:2.3:a:naver:comic_viewer:*:*:*:*:*:*:*:*

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