How severe is CVE-2019-13611?

CVE-2019-13611 has a CVSS score of 8.8/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2019-13611?

CVE-2019-13611 affects the following packages: python-engineio (PyPI). Ecosystems affected: PyPI.

How do I fix CVE-2019-13611?

Update python-engineio to 3.9.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2019-13611 is resolved across your whole dependency graph.

How do I detect CVE-2019-13611 in my PyPI dependencies?

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

How do I mitigate CVE-2019-13611 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-2019-13611 actively exploited in the wild?

No public exploit code has been indexed for CVE-2019-13611 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-2019-13611?

CVE-2019-13611 has an EPSS (Exploit Prediction Scoring System) score of 0.9%, placing it in the 58th 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-2019-13611?

CVE-2019-13611 is classified as Cross-Site Request Forgery (CSRF) (CWE-352). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2019-13611 published, and has it been updated?

CVE-2019-13611 was published on July 16, 2019 and was last updated on October 20, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐍

🐍 PyPI

Not in CISA KEV

HIGH severity

CVE-2019-13611 — python-engineio

HIGH

CVE-2019-13611 is a high-severity (CVSS 8.8) Cross-Site Request Forgery (CSRF) vulnerability in python-engineio. A fix is available for python-engineio — see the affected versions and patch details below.

python-engineio vulnerable to Cross-Site Request Forgery (CSRF)

Also known asGHSA-j3jp-gvr5-7hwqPYSEC-2019-170

Published

Jul 16, 2019

Updated

Oct 20, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Oct 23, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

0.9%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs58th percentile — riskier than 58% of all scored CVEsHighest risk

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

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

1 pkg affected

🐍python-engineio

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

Description

WebSocket cross-origin vulnerability

Impact

This is a Cross-Site Request Forgery (CSRF) vulnerability. It affects Socket.IO and Engine.IO web servers that authenticate clients using cookies.

Patches

python-engineio version 3.9.0 patches this vulnerability by adding server-side Origin header checks.

Workarounds

Do not use cookies for client authentication, or else add a CSRF token to the connection URL.

References

https://www.owasp.org/index.php/Cross-Site_Request_Forgery_(CSRF) https://www.christian-schneider.net/CrossSiteWebSocketHijacking.html

For more information

If you have any questions or comments about this advisory:

Open an issue in python-engineio

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐍PyPI	`python-engineio`	all versions	3.9.0`pip install --upgrade 'python-engineio==3.9.0'`

Affected Products

1 product · 1 configurations

Application

python-engineiopython-engineio_project

≤ 3.8.2

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for python-engineio, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update python-engineio to 3.9.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2019-13611 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

## WebSocket cross-origin vulnerability ### Impact This is a Cross-Site Request Forgery (CSRF) vulnerability. It affects Socket.IO and Engine.IO web servers that authenticate clients using cookies. ### Patches python-engineio version 3.9.0 patches this vulnerability by adding server-side Origin header checks. ### Workarounds Do not use cookies for client authentication, or else add a CSRF token to the connection URL. ### References https://www.owasp.org/index.php/Cross-Site_Request_Forgery_(CSRF) https://www.christian-schneider.net/CrossSiteWebSocketHijacking.html ### For more information