CVE-2020-9487 Missing Authentication for Critical Function in Apache NiFi

What is CVE-2020-9487?

CVE-2020-9487 is a high-severity denial of service vulnerability in Apache Nifi, published on 1 Oct 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official 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.

Weakness: CWE-306

Which versions are affected by CVE-2020-9487?

3 open source packages ship an affected version, including org.apache.nifi:nifi and nifi. It affects 1 product.

Products include Apache Nifi.

How do I fix CVE-2020-9487?

Upgrade org.apache.nifi:nifi to 1.12.0-RC1 or later.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2020-9487 being exploited?

There is no known exploitation of CVE-2020-9487 in the wild and no public exploit code.

Other vulnerabilities in Apache Nifi

• CVE-2018-1309 Improper Restriction of XML External Entity Reference in Apache NiFi Critical 9.8
• CVE-2017-15697 Apache NiFi XSS issue in context path handling Critical 9.8
• CVE-2017-5636 Injection in Apache NiFi Critical 9.8
• CVE-2026-68981 Apache NiFi: Uncontrolled Resource Consumption through Decompression of HTTP Requests High 8.8
• CVE-2023-36542 Apache NiFi: Potential Code Injection with Properties Referencing Remote Resources High 8.8

All Apache Nifi vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BIT-nifi-2020-9487, GHSA-3pp3-77j6-8ph6.