How severe is CVE-2021-26617?

CVE-2021-26617 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-26617 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-26617?

CVE-2021-26617 affects Firstmall. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-26617?

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-2021-26617 published?

CVE-2021-26617 was published on 2022-02-25 and last updated on 2026-06-17.

CVE-2021-26617

CVE-2021-26617 is a high-severity vulnerability in Firstmall with a CVSS 3.x base score of 8.1. 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 8.1)
CVSS v2: 7.5
EPSS exploit prediction: 1% (66th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Firstmall
Published: 2022-02-25
Last modified: 2026-06-17

Description

This issues due to insufficient verification of the various input values from user’s input. The vulnerability allows remote attackers to execute malicious code in Firstmall via navercheckout_add function.

Frequently asked questions

What is CVE-2021-26617?: This issues due to insufficient verification of the various input values from user’s input. The vulnerability allows remote attackers to execute malicious code in Firstmall via navercheckout_add function.
How severe is CVE-2021-26617?: CVE-2021-26617 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-26617 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-26617?: CVE-2021-26617 affects Firstmall. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-26617?: 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-2021-26617 published?: CVE-2021-26617 was published on 2022-02-25 and last updated on 2026-06-17.

References

https://www.krcert.or.kr/krcert/secNoticeView.do?bulletin_writing_sequence=36469

Affected products (1)

cpe:2.3:a:firstmall:firstmall:-:*:*:*:*:*:*:*

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