How severe is CVE-2020-9487?

CVE-2020-9487 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 none, and availability high.

Is CVE-2020-9487 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-9487?

CVE-2020-9487 affects Apache Nifi. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-9487?

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-2020-9487 published?

CVE-2020-9487 was published on 2020-10-01 and last updated on 2026-06-17.

CVE-2020-9487

CVE-2020-9487 is a high-severity vulnerability in Apache Nifi 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-306.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 3% (87th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-306
Affected product: Apache Nifi
Published: 2020-10-01
Last modified: 2026-06-17

Description

In Apache NiFi 1.0.0 to 1.11.4, the NiFi download token (one-time password) mechanism used a fixed cache size and did not authenticate a request to create a download token, only when attempting to use the token to access the content. An unauthenticated user could repeatedly request download tokens, preventing legitimate users from requesting download tokens.

Frequently asked questions

What is CVE-2020-9487?: In Apache NiFi 1.0.0 to 1.11.4, the NiFi download token (one-time password) mechanism used a fixed cache size and did not authenticate a request to create a download token, only when attempting to use the token to access the content. An unauthenticated user could repeatedly request download tokens, preventing legitimate users from requesting download tokens.
How severe is CVE-2020-9487?: CVE-2020-9487 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 none, and availability high.
Is CVE-2020-9487 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-9487?: CVE-2020-9487 affects Apache Nifi. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-9487?: 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-2020-9487 published?: CVE-2020-9487 was published on 2020-10-01 and last updated on 2026-06-17.

References

https://nifi.apache.org/security#CVE-2020-9487

Affected products (1)

cpe:2.3:a:apache:nifi:*:*:*:*:*:*:*:*

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