How severe is CVE-2021-31703?

CVE-2021-31703 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-2021-31703 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-31703?

CVE-2021-31703 affects Frontiersoftware Ichris. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-31703?

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-2021-31703 published?

CVE-2021-31703 was published on 2021-05-29 and last updated on 2026-06-17.

CVE-2021-31703

CVE-2021-31703 is a critical-severity vulnerability in Frontiersoftware Ichris 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. The underlying weakness is classified as CWE-434.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 1% (65th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-434
Affected product: Frontiersoftware Ichris
Published: 2021-05-29
Last modified: 2026-06-17

Description

Frontier ichris through 5.18 allows users to upload malicious executable files that might later be downloaded and run by any client user.

Frequently asked questions

What is CVE-2021-31703?: Frontier ichris through 5.18 allows users to upload malicious executable files that might later be downloaded and run by any client user.
How severe is CVE-2021-31703?: CVE-2021-31703 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-2021-31703 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-31703?: CVE-2021-31703 affects Frontiersoftware Ichris. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-31703?: 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-2021-31703 published?: CVE-2021-31703 was published on 2021-05-29 and last updated on 2026-06-17.

References

https://github.com/l00neyhacker/CVE-2021-31703

Affected products (1)

cpe:2.3:a:frontiersoftware:ichris:*:*:*:*:*:*:*:*

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