How severe is CVE-2021-23597?

CVE-2021-23597 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-2021-23597 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-23597?

CVE-2021-23597 affects Fastify Fastify-multipart. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-23597?

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-2021-23597 published?

CVE-2021-23597 was published on 2022-02-11 and last updated on 2026-06-17.

CVE-2021-23597

CVE-2021-23597 is a high-severity vulnerability in Fastify Fastify-multipart 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-1321.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (79th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1321
Affected product: Fastify Fastify-multipart
Published: 2022-02-11
Last modified: 2026-06-17

Description

This affects the package fastify-multipart before 5.3.1. By providing a name=constructor property it is still possible to crash the application. **Note:** This is a bypass of CVE-2020-8136 (https://security.snyk.io/vuln/SNYK-JS-FASTIFYMULTIPART-1290382).

Frequently asked questions

What is CVE-2021-23597?: This affects the package fastify-multipart before 5.3.1. By providing a name=constructor property it is still possible to crash the application. **Note:** This is a bypass of CVE-2020-8136 (https://security.snyk.io/vuln/SNYK-JS-FASTIFYMULTIPART-1290382).
How severe is CVE-2021-23597?: CVE-2021-23597 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-2021-23597 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-23597?: CVE-2021-23597 affects Fastify Fastify-multipart. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-23597?: 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-2021-23597 published?: CVE-2021-23597 was published on 2022-02-11 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:fastify:fastify-multipart:*:*:*:*:*:fastify:*:*

More vulnerabilities in Fastify Fastify-multipart

CVE-2023-25576 — High (CVSS 7.5): @fastify/multipart is a Fastify plugin to parse the multipart content-type. Prior to versions 7.4.1 and 6.0.1,…
CVE-2020-8136 — High (CVSS 7.5): Prototype pollution vulnerability in fastify-multipart < 1.0.5 allows an attacker to crash fastify applications parsing…

All CVEs affecting Fastify Fastify-multipart →

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