What is CVE-2021-32742?

CVE-2021-32742 is a high-severity vulnerability in Vapor, classified under Deserialization of Untrusted Data. CVSS score: 7.5/10. Published 2021-07-09.

How severe is CVE-2021-32742?

High severity. CVSS v3 base score is 7.5 out of 10.

Deserialization in Vapor

CVE-2021-32742

Vapor is a web framework for Swift. In versions 4.47.1 and prior, bug in the `Data.init(base32Encoded:)` function opens up the potential for exposing server memory and/or crashing the server (Denial of Service) for applications where untrusted data can end up in said function. Vapor does not currently use this function itself so this only impact applications that use the impacted function directly or through other dependencies. The vulnerability is patched in version 4.47.2. As a workaround, one may use an alternative to Vapor's built-in `Data.init(base32Encoded:)`.

Vulnerability class: Insecure Deserialization

Published 2021-07-09 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.012 (66.9th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 67th percentile — 66.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.012 · newest: 0.012 · change: 0.000

Affected products

Vapor — versions <= 4.47.1
Vapor Project

Weakness classification (CWE)

CWE-502 — Deserialization of Untrusted Data

References

github.com/vapor/vapor/security/advisories/GHSA-pqwh-c2f3-vxmq (Third Party Advisory)
github.com/vapor/vapor/releases/tag/4.47.2 (Third Party Advisory, Release Notes)

Frequently asked questions

What is CVE-2021-32742?: CVE-2021-32742 is a high-severity vulnerability in Vapor, classified under Deserialization of Untrusted Data. CVSS score: 7.5/10. Published 2021-07-09.
How severe is CVE-2021-32742?: High severity. CVSS v3 base score is 7.5 out of 10.