CVE-2021-23597

mediumpriority · track · 31EPSS 0.020 · 81 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

2.03% (81st) EPSS

CVSS 5 · medium

Is it mine?

3 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · osv · nvd

EPSS · scored 2026-10-28

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).

cvss

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Psecondary · ENISA EU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · report@snyk.ioexploitability 3.9 · impact 3.6

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · OSV

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-1321USprimaryCWE-400US

affected products (3)

Products and version ranges known to be affected.

n/a fastify-multipartunspecified → 5.3.1enisa_euvdEU
fastify fastify-multipart< 5.3.1nvdUScpe:2.3:a:fastify:fastify-multipart:*:*:*:*:*:*:*:*
npm fastify-multipart< 5.3.1osvUSpkg:npm/fastify-multipart

advisories (1)

Vendor and ecosystem advisories describing this.

GHSA-qh73-qc3p-rjv2Uncaught Exception in fastify-multipart2022-02-11ghsa · osvUS
### Impact This is a bypass of CVE-2020-8136 (https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-8136). By providing a `name=constructor` property it is still possible to crash the application. The original fix only checks for the key `__proto__` (https://github.com/fastify/fastify-multipart/pull/116). All users are recommended to upgrade ### Patches v5.3.1 includes a patch ### Workarounds No workarounds are possible. ### References Read up https://www.fastify.io/docs/latest/Guides/Prototype-Poisoning/ ### For more information If you have any questions or comments about this advisory: * Open an issue in [https://github.com/fastify/fastify-multipart](https://github.com/fastify/fastify-multipart) * Email us at [hello@matteocollina.com](mailto:hello@matteocollina.com)

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd osv nvd NVD CVE.org MITRE

published 2022-02-11modified 2026-06-17

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+710 more

references (10)

External citations — patches, advisories, analysis.

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