CVE-2025-0938

URL parser allowed square brackets in domain names

At a glance

Severity
MEDIUM 6.3
EPSS
EPSS 1.56 % · percentile 75 (2026-10-27)
State
PUBLISHED
Published
Updated
Assigner
PSF
NVD status
Deferred

Description

The Python standard library functions `urllib.parse.urlsplit` and `urlparse` accepted domain names that included square brackets which isn't valid according to RFC 3986. Square brackets are only meant to be used as delimiters for specifying IPv6 and IPvFuture hosts in URLs. This could result in differential parsing across the Python URL parser and other specification-compliant URL parsers.

Scores

VersionScoreVectorScored by
CVSS 4.0MEDIUM 6.3CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:NPSF
CVSS 4.0MEDIUM 6.3CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XNVD · cna@python.org (Secondary)

Weaknesses (CWE)

European references

CERT-FR advisories

Affected products

ProductVersions
Python Software Foundation · CPythonaffected 0 < 3.9.22 ; affected 3.10.0 < 3.10.17 ; affected 3.11.0 < 3.11.12 ; affected 3.12.0 < 3.12.9 ; affected 3.13.0 < 3.13.2 ; affected 3.14.0a1 < 3.14.0a5

References

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD