| Name | CVE-2026-7210 |
| 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. |
| Source | CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|
| pypy3 (PTS) | bullseye | 7.3.5+dfsg-2+deb11u2 | vulnerable |
| bullseye (security) | 7.3.5+dfsg-2+deb11u5 | vulnerable |
| bookworm | 7.3.11+dfsg-2+deb12u3 | vulnerable |
| trixie | 7.3.19+dfsg-2 | vulnerable |
| forky, sid | 7.3.23+dfsg-1 | vulnerable |
| python2.7 (PTS) | bullseye | 2.7.18-8+deb11u1 | vulnerable |
| python3.11 (PTS) | bookworm | 3.11.2-6+deb12u7 | vulnerable |
| bookworm (security) | 3.11.2-6+deb12u3 | vulnerable |
| python3.13 (PTS) | trixie | 3.13.5-2+deb13u2 | vulnerable |
| forky, sid | 3.13.12-1 | vulnerable |
| python3.14 (PTS) | forky, sid | 3.14.5-1 | vulnerable |
| python3.9 (PTS) | bullseye | 3.9.2-1 | vulnerable |
| bullseye (security) | 3.9.2-1+deb11u7 | vulnerable |
The information below is based on the following data on fixed versions.
Notes
[trixie] - python3.13 <no-dsa> (Minor issue)
[bookworm] - python3.11 <no-dsa> (Minor issue)
[bullseye] - python3.9 <postponed> (Minor issue, wait for expat update)
[bullseye] - python2.7 <end-of-life> (not supported in bullseye)
[trixie] - pypy3 <no-dsa> (Minor issue)
[bookworm] - pypy3 <no-dsa> (Minor issue)
[bullseye] - pypy3 <postponed> (Minor issue)
https://mail.python.org/archives/list/security-announce@python.org/thread/PNY5OMBDPM2FRUZTWFFPJ6LISWKV627K/
https://github.com/python/cpython/issues/149018
https://github.com/python/cpython/pull/149023
https://github.com/python/cpython/commit/24b8f12544468e4cedf5bfbe25442fcd495391e4 (main)
https://github.com/python/cpython/pull/149645 (3.15)
https://github.com/python/cpython/pull/149646 (3.14)
Fully mitigating this vulnerability requires fixing both libexpat
(CVE-2026-41080) and applying the python patch for CVE-2026-7210.