CVE-2026-7210

The expat and elementtree parsers use insufficient entropy for XML hash-flooding protection

At a glance

Severity: MEDIUM 6.3
EPSS: EPSS 0.67 % · percentile 52 (2026-10-27)
State: PUBLISHED
Published: 2026-05-11
Updated: 2026-10-02
Assigner: PSF
NVD status: Modified

Description

`xml.parsers.expat` and `xml.etree.ElementTree` use insufficient entropy for Expat hash-flooding protection, which allows a crafted XML document to trigger hash flooding.\r\n\r\nFully mitigating this vulnerability requires both updating libexpat to 2.8.0 or later and applying this patch.

Scores

Version	Score	Vector	Scored by
CVSS 4.0	MEDIUM 6.3	CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N	PSF
CVSS 4.0	MEDIUM 6.3	CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/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:X	NVD · cna@python.org (Secondary)
CVSS 3.1	HIGH 7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H	NVD · nvd@nist.gov (Primary)

Weaknesses (CWE)

CWE-331

European references

ENISA EUVD · EUVD-2026-29178
GCVE · GCVE-0-2026-7210

CERT-FR advisories

CERTFR-2026-AVI-1385 — Multiples vulnérabilités dans les produits VMware · cert.ssi.gouv.fr
CERTFR-2026-AVI-0560 — Vulnérabilité dans CPython · cert.ssi.gouv.fr

Affected configurations (NVD CPE)

cpe:2.3:a:python:python:*:*:*:*:*:*:*:* < 3.13.14
cpe:2.3:a:python:python:*:*:*:*:*:*:*:* ≥ 3.14.0 < 3.14.6
cpe:2.3:a:python:python:3.15.0:alpha1:*:*:*:*:*:*
cpe:2.3:a:python:python:3.15.0:alpha2:*:*:*:*:*:*
cpe:2.3:a:python:python:3.15.0:alpha3:*:*:*:*:*:*
cpe:2.3:a:python:python:3.15.0:alpha4:*:*:*:*:*:*
cpe:2.3:a:python:python:3.15.0:alpha5:*:*:*:*:*:*
cpe:2.3:a:python:python:3.15.0:alpha6:*:*:*:*:*:*
cpe:2.3:a:python:python:3.15.0:alpha7:*:*:*:*:*:*
cpe:2.3:a:python:python:3.15.0:alpha8:*:*:*:*:*:*
cpe:2.3:a:python:python:3.15.0:beta1:*:*:*:*:*:*

Affected products

Product	Versions
Python Software Foundation · CPython	affected 0 < 3.10.22 ; affected 3.11.0 < 3.11.16 ; affected 3.12.0 < 3.12.14 ; affected 3.13.0 < 3.13.14 ; affected 3.14.0 < 3.14.6 ; affected 3.15.0a1 < 3.15.0b2

References

Sources

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