How severe is CVE-2020-26229?

CVE-2020-26229 has a CVSS score of 3.7/10, rated LOW. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2020-26229?

CVE-2020-26229 affects the following packages: typo3/cms-core (Packagist), typo3/cms (Packagist). Ecosystems affected: Packagist.

How do I fix CVE-2020-26229?

Update typo3/cms-core to 10.4.10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-26229 is resolved across your whole dependency graph.

How do I detect CVE-2020-26229 in my Packagist dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for typo3/cms-core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2020-26229 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Is CVE-2020-26229 actively exploited in the wild?

No public exploit code has been indexed for CVE-2020-26229 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2020-26229?

CVE-2020-26229 has an EPSS (Exploit Prediction Scoring System) score of 0.6%, placing it in the 49th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2020-26229?

CVE-2020-26229 is classified as XML External Entity (XXE) (CWE-611). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2020-26229 published, and has it been updated?

CVE-2020-26229 was published on November 23, 2020 and was last updated on August 27, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐘

🐘 Packagist

Not in CISA KEV

LOW severity

CVE-2020-26229 — cms-core

LOW

CVE-2020-26229 is a low-severity (CVSS 3.7) XML External Entity (XXE) vulnerability in typo3/cms-core. A fix is available for typo3/cms-core — see the affected versions and patch details below.

XML External Entity in Dashboard Widget

Also known asBIT-typo3-2020-26229GHSA-q9cp-mc96-m4w2

Published

Nov 23, 2020

Updated

Aug 27, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

Exploitation data as of Oct 10, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

0.6%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs49th percentile — riskier than 49% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2020-26229 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 385,386 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

2 pkgs affected

🐘typo3/cms-core🐘typo3/cms

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.

Description

TYPO3 is an open source PHP based web content management system. In TYPO3 from version 10.4.0, and before version 10.4.10, RSS widgets are susceptible to XML external entity processing. This vulnerability is reasonable, but is theoretical - it was not possible to actually reproduce the vulnerability with current PHP versions of supported and maintained system distributions. At least with libxml2 version 2.9, the processing of XML external entities is disabled per default - and cannot be exploited. Besides that, a valid backend user account is needed. Update to TYPO3 version 10.4.10 to fix the problem described.

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`typo3/cms-core`	≥ 10.0.0&&< 10.4.10	10.4.10`composer require typo3/cms-core:^10.4.10`
🐘Packagist	`typo3/cms`	≥ 10.0.0&&< 10.4.10	10.4.10`composer require typo3/cms:^10.4.10`

Affected Products

1 product · 1 configurations

Application

typo3typo3

≥ 10.0.0 && < 10.4.10

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for typo3/cms-core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update typo3/cms-core to 10.4.10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-26229 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is CVE-2020-26229 in your dependencies?

Find it across Packagist, including transitive dependencies.

Scan my dependencies How O3 SCA works

CVSS Score

3.7/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

High

Privileges Required

Low

User Interaction

Required

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

Low

Raw vector

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

CWE Classification

CWE-611XML External Entity (XXE)

Weaponization

No known public exploit tooling found.

OpenSSF Scorecard

Package health score

TYPO3.CMS

6.0/10

Code-Review10/10

Maintained10/10

Branch-Protection0/10

Assessed Oct 5, 2026

Timeline

Disclosed

Nov 23, 2020

Last updated

Aug 27, 2026

Identifiers

CVE-2020-26229

GHSA-q9cp-mc96-m4w2

BIT-typo3-2020-26229

References

Advisorygithub.com Advisorytypo3.org Advisorynvd.nist.gov Webgithub.com Webgithub.com

Related vulnerabilities

This CVE is low severity; 8 of 8 other CVEs affecting typo3/cms-core are rated as high or higher (top: high).

CVE-2026-19418CVE-2026-47352CVE-2026-47347CVE-2026-47343CVE-2026-49740CVE-2026-47348CVE-2026-49742CVE-2026-47349

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedAug 27, 2026