How severe is CVE-2021-27670?

CVE-2021-27670 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-2021-27670 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 61% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-27670?

CVE-2021-27670 affects Appspace. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-27670?

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-2021-27670 published?

CVE-2021-27670 was published on 2021-02-25 and last updated on 2026-06-17.

CVE-2021-27670

CVE-2021-27670 is a critical-severity vulnerability in Appspace with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 61% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-918.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 61% (99th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-918
Affected product: Appspace
Published: 2021-02-25
Last modified: 2026-06-17

Description

Appspace 6.2.4 allows SSRF via the api/v1/core/proxy/jsonprequest url parameter.

Frequently asked questions

What is CVE-2021-27670?: Appspace 6.2.4 allows SSRF via the api/v1/core/proxy/jsonprequest url parameter.
How severe is CVE-2021-27670?: CVE-2021-27670 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-2021-27670 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 61% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-27670?: CVE-2021-27670 affects Appspace. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-27670?: 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-2021-27670 published?: CVE-2021-27670 was published on 2021-02-25 and last updated on 2026-06-17.

References

https://github.com/h3110mb/PoCSSrfApp

Affected products (1)

cpe:2.3:a:appspace:appspace:6.2.4:*:*:*:*:*:*:*

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