How severe is CVE-2021-26605?

CVE-2021-26605 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 high, and availability none.

Is CVE-2021-26605 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-26605?

CVE-2021-26605 affects Unidocs Ezpdfreader. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-26605?

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-2021-26605 published?

CVE-2021-26605 was published on 2021-08-05 and last updated on 2026-06-17.

CVE-2021-26605

CVE-2021-26605 is a high-severity vulnerability in Unidocs Ezpdfreader 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-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.5
EPSS exploit prediction: 1% (60th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Unidocs Ezpdfreader
Published: 2021-08-05
Last modified: 2026-06-17

Description

An improper input validation vulnerability in the service of ezPDFReader allows attacker to execute arbitrary command. This issue occurred when the ezPDF launcher received and executed crafted input values through JSON-RPC communication.

Frequently asked questions

What is CVE-2021-26605?: An improper input validation vulnerability in the service of ezPDFReader allows attacker to execute arbitrary command. This issue occurred when the ezPDF launcher received and executed crafted input values through JSON-RPC communication.
How severe is CVE-2021-26605?: CVE-2021-26605 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 high, and availability none.
Is CVE-2021-26605 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-26605?: CVE-2021-26605 affects Unidocs Ezpdfreader. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-26605?: 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-2021-26605 published?: CVE-2021-26605 was published on 2021-08-05 and last updated on 2026-06-17.

References

https://www.boho.or.kr/krcert/secNoticeView.do?bulletin_writing_sequence=36168

Affected products (1)

cpe:2.3:a:unidocs:ezpdfreader:*:*:*:*:*:*:*:*

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