CVE-2021-29510

3.3 LOW
Published: May 13, 2021 Modified: December 08, 2025

Description

Pydantic is a data validation and settings management using Python type hinting. In affected versions passing either `'infinity'`, `'inf'` or `float('inf')` (or their negatives) to `datetime` or `date` fields causes validation to run forever with 100% CPU usage (on one CPU). Pydantic has been patched with fixes available in the following versions: v1.8.2, v1.7.4, v1.6.2. All these versions are available on pypi(https://pypi.org/project/pydantic/#history), and will be available on conda-forge(https://anaconda.org/conda-forge/pydantic) soon. See the changelog(https://pydantic-docs.helpmanual.io/) for details. If you absolutely can't upgrade, you can work around this risk using a validator(https://pydantic-docs.helpmanual.io/usage/validators/) to catch these values. This is not an ideal solution (in particular you'll need a slightly different function for datetimes), instead of a hack like this you should upgrade pydantic. If you are not using v1.8.x, v1.7.x or v1.6.x and are unable to upgrade to a fixed version of pydantic, please create an issue at https://github.com/samuelcolvin/pydantic/issues requesting a back-port, and we will endeavour to release a patch for earlier versions of pydantic.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://github.com/samuelcolvin/pydantic/commit/7e83fdd2563ffac081db7ecdf1affa65ef38c468
Source: security-advisories@github.com
Patch Third Party Advisory
https://github.com/samuelcolvin/pydantic/security/advisories/GHSA-5jqp-qgf6-3pvh
Source: security-advisories@github.com
Mitigation Patch Third Party Advisory
https://github.com/samuelcolvin/pydantic/commit/7e83fdd2563ffac081db7ecdf1affa65ef38c468
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Third Party Advisory
https://github.com/samuelcolvin/pydantic/security/advisories/GHSA-5jqp-qgf6-3pvh
Source: af854a3a-2127-422b-91ae-364da2661108
Mitigation Patch Third Party Advisory

10 reference(s) from NVD

Quick Stats

CVSS v3 Score
3.3 / 10.0
EPSS (Exploit Probability)
0.1%
21th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

pydantic fedoraproject