How severe is CVE-2020-19000?

CVE-2020-19000 has a CVSS score of 6.1/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2020-19000?

CVE-2020-19000 affects the following packages: simiki (PyPI). Ecosystems affected: PyPI.

How do I fix CVE-2020-19000?

Update simiki to 1.6.2.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-19000 is resolved across your whole dependency graph.

How do I detect CVE-2020-19000 in my PyPI dependencies?

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

How do I mitigate CVE-2020-19000 if there is no patch (or I can't update yet)?

Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Is CVE-2020-19000 actively exploited in the wild?

Yes. There are 1 known exploit references for CVE-2020-19000, including 1 in-the-wild exploitation observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2020-19000?

CVE-2020-19000 has an EPSS (Exploit Prediction Scoring System) score of 1.1%, placing it in the 65th 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-2020-19000?

CVE-2020-19000 is classified as Cross-site Scripting (XSS) (CWE-79). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2020-19000 published, and has it been updated?

CVE-2020-19000 was published on August 27, 2021 and was last updated on July 8, 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

MEDIUM severity

CVE-2020-19000 — simiki

MEDIUM

CVE-2020-19000 is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in simiki. 1 public exploit reference exists, so weaponization risk is real. A fix is available for simiki — see the affected versions and patch details below.

Cross Site Scripting (XSS) in Simiki

Also known asGHSA-fqr5-qphf-vfr8PYSEC-2021-347

Published

Aug 27, 2021

Updated

Jul 8, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

1 known

Exploitation data as of Oct 12, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

1.1%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs65th percentile — riskier than 65% of all scored CVEsHighest risk

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

How urgent is this, really

CVE-2020-19000 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 385,987 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

1 pkg affected

🐍simiki

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

Cross Site Scripting (XSS) in Simiki v1.6.2.1 and prior allows remote attackers to execute arbitrary code via line 54 of the component 'simiki/blob/master/simiki/generators.py'.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐍PyPI	`simiki`	all versions	1.6.2.2`pip install --upgrade 'simiki==1.6.2.2'`

Affected Products

1 product · 1 configurations

Application

simikisimiki_project

1 version

1.6.2.1

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

Cross Site Scripting (XSS) in Simiki v1.6.2.1 and prior allows remote at…

github.comNVDSep 2021

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for simiki, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update simiki to 1.6.2.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-19000 is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Frequently Asked Questions

Cross Site Scripting (XSS) in Simiki v1.6.2.1 and prior allows remote attackers to execute arbitrary code via line 54 of the component 'simiki/blob/master/simiki/generators.py'.

O3 Security · Impact-Aware SCA

Is CVE-2020-19000 in your dependencies?

Find it across PyPI, including transitive dependencies.

Scan my dependencies How O3 SCA works

CVSS Score

6.1/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Raw vector

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

CWE Classification

CWE-79Cross-site Scripting (XSS)

Weaponization

No known public exploit tooling found.

OpenSSF Scorecard

Package health score

simiki

1.8/10

Code-Review0/10

Maintained0/10

Branch-Protection0/10

Assessed Oct 5, 2026

Timeline

Disclosed

Aug 27, 2021

First exploit

Sep 1, 2021

4 days after disclosure — rapid exploitation

Last updated

Jul 8, 2026

Identifiers

CVE-2020-19000

GHSA-fqr5-qphf-vfr8

PYSEC-2021-347

References

Advisorynvd.nist.gov Reportgithub.com Webgithub.com Packagegithub.com

Related vulnerabilities

Also affects simiki

This CVE is medium severity; 1 of 1 other CVE affecting simiki is rated as high or higher (top: critical).

CVE-2020-19001

Same weakness: CWE-79

This CVE is medium severity; 7 of 7 other CVEs with CWE-79 are rated as high or higher (top: high).

CVE-2026-91127CVE-2026-77606CVE-2026-84992CVE-2026-77608CVE-2026-77607GHSA-9rcc-pmj8-ffhrCVE-2026-77616Browse all CWE-79

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedJul 8, 2026