CVE-2026-7210

medium

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.

References

Advisories
More

https://mail.python.org/archives/list/[email protected]/thread/PNY5OMBDPM2FRUZTWFFPJ6LISWKV627K/

http://www.openwall.com/lists/oss-security/2026/05/11/8

http://www.openwall.com/lists/oss-security/2026/05/11/13

https://github.com/python/cpython/pull/149023

https://github.com/python/cpython/issues/149018

https://github.com/python/cpython/commit/fc9b11ff49cbc82e6f917d07a61517a2b5f3145f

https://github.com/python/cpython/commit/eeea765cb9d8f1fc3d8918b272ac3c477983f27a

https://github.com/python/cpython/commit/3573b3b1ecbd99030a0b18658e1bfece771b2566

https://github.com/python/cpython/commit/24b8f12544468e4cedf5bfbe25442fcd495391e4

Details

Source: Mitre, NVD

Published: 2026-05-11

Updated: 2026-06-15

Risk Information

CVSS v2

Base Score: 7.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C

Severity: High

CVSS v3

Base Score: 7.5

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Severity: High

CVSS v4

Base Score: 6.3

Vector: 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

Severity: Medium

EPSS

EPSS: 0.00045