HOMEVULNERABILITIESCVE-2026-7210
CRITICAL

CVE-2026-7210

CWE-331Published: May 11, 2026· Updated: May 16, 2026

9.8
CVSS v3.1
EPSS:0.04%probability of exploitation in 30 daysPercentile:13.9th

Official 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.

NVD Source

Technical Analysis

CVE-2026-7210 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 9.8.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected Vendors & Products

libexpat_project1 product
libexpat
Source: NVD CPE · 1 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
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Official Patches & Advisories

PATCHhttps://github.com/python/cpython/pull/149023
ADVISORYhttps://mail.python.org/archives/list/[email protected]/thread/PNY5OMBDPM2FRUZTWFFPJ6LISWKV627K/
ADVISORYhttp://www.openwall.com/lists/oss-security/2026/05/11/13
ADVISORYhttp://www.openwall.com/lists/oss-security/2026/05/11/8

All References (5)

→
https://github.com/python/cpython/issues/149018Issue Tracking
→
https://github.com/python/cpython/pull/149023Issue Tracking · Patch
→
https://mail.python.org/archives/list/[email protected]/thread/PNY5OMBDPM2FRUZTWFFPJ6LISWKV627K/Mailing List · Third Party Advisory
→
http://www.openwall.com/lists/oss-security/2026/05/11/13Mailing List · Third Party Advisory
→
http://www.openwall.com/lists/oss-security/2026/05/11/8Mailing List · Third Party Advisory

Quick Facts

CVE IDCVE-2026-7210
CVSS Score9.8 / 10
SeverityCRITICAL
WeaknessCWE-331
CISA KEVNo
EPSS (30d)0.04%
Affected1 vendor
PublishedMay 11, 2026

Related CVEs (CWE-331)

CVE-2026-34236
9.8
CVE-2026-4827
8.7
CVE-2026-2336
8.7
CVE-2026-46473
7.5
CVE-2026-46474
7.5
CVE-2026-8700
7.3

Recommended Actions

  • →Apply vendor patches immediately
  • →Monitor CVE-2026-7210 in threat intel feeds
  • →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.
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