","image":"https://o3.security/opengraph.png","datePublished":"2018-12-20T00:29:00.303Z","dateModified":"2026-10-20T10:49:30.392177470Z","url":"https://o3.security/vulnerability/CVE-2018-20302","inLanguage":"en","author":{"@id":"https://o3.security/#organization"},"publisher":{"@id":"https://o3.security/#organization"},"mainEntityOfPage":{"@type":"WebPage","@id":"https://o3.security/vulnerability/CVE-2018-20302"},"speakable":{"@type":"SpeakableSpecification","cssSelector":["h1",".vuln-summary",".vuln-severity",".vuln-mitigation"]},"about":[{"@type":"SoftwareApplication","name":"xain","applicationCategory":"Hex","softwareVersion":"0.6.2"}],"citation":[{"@type":"CreativeWork","name":"NVD","url":"https://nvd.nist.gov/vuln/detail/CVE-2018-20302"},{"@type":"CreativeWork","name":"OSV.dev","url":"https://osv.dev/vulnerability/CVE-2018-20302"},{"@type":"CreativeWork","name":"FIRST.org EPSS","url":"https://www.first.org/epss/api-data?cve=CVE-2018-20302"}]}","url":"https://o3.security/vulnerability/CVE-2018-20302","identifier":"CVE-2018-20302","datePublished":"2018-12-20T00:29:00.303Z","dateModified":"2026-10-20T10:49:30.392177470Z","inLanguage":"en","license":"https://creativecommons.org/licenses/by/4.0/","keywords":["CVE-2018-20302","MEDIUM severity","CWE-79","CVE","vulnerability","security advisory"],"creator":{"@id":"https://o3.security/#organization"},"isAccessibleForFree":true,"citation":[{"@type":"CreativeWork","name":"NVD","url":"https://nvd.nist.gov/vuln/detail/CVE-2018-20302"},{"@type":"CreativeWork","name":"OSV.dev","url":"https://osv.dev/vulnerability/CVE-2018-20302"},{"@type":"CreativeWork","name":"FIRST.org EPSS","url":"https://www.first.org/epss/api-data?cve=CVE-2018-20302"}],"variableMeasured":[{"@type":"PropertyValue","name":"CVSS Base Score","value":6.1,"description":"CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"},{"@type":"PropertyValue","name":"Severity","value":"MEDIUM"},{"@type":"PropertyValue","name":"EPSS Percentile","value":59}]}\n ```"}},{"@type":"Question","name":"How severe is CVE-2018-20302?","acceptedAnswer":{"@type":"Answer","text":"CVE-2018-20302 has a CVSS score of 6.1/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance."}},{"@type":"Question","name":"Which packages are affected by CVE-2018-20302?","acceptedAnswer":{"@type":"Answer","text":"CVE-2018-20302 affects the following packages: xain (Hex). Ecosystems affected: Hex."}},{"@type":"Question","name":"How do I fix CVE-2018-20302?","acceptedAnswer":{"@type":"Answer","text":"Update xain to 0.6.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2018-20302 is resolved across your whole dependency graph."}},{"@type":"Question","name":"How do I detect CVE-2018-20302 in my Hex dependencies?","acceptedAnswer":{"@type":"Answer","text":"Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for xain, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version."}},{"@type":"Question","name":"How do I mitigate CVE-2018-20302 if there is no patch (or I can't update yet)?","acceptedAnswer":{"@type":"Answer","text":"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."}},{"@type":"Question","name":"Is CVE-2018-20302 actively exploited in the wild?","acceptedAnswer":{"@type":"Answer","text":"Yes. There are 1 known exploit references for CVE-2018-20302, 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."}},{"@type":"Question","name":"What is the EPSS score for CVE-2018-20302?","acceptedAnswer":{"@type":"Answer","text":"CVE-2018-20302 has an EPSS (Exploit Prediction Scoring System) score of 0.9%, placing it in the 59th 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."}},{"@type":"Question","name":"What type of vulnerability is CVE-2018-20302?","acceptedAnswer":{"@type":"Answer","text":"CVE-2018-20302 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."}},{"@type":"Question","name":"When was CVE-2018-20302 published, and has it been updated?","acceptedAnswer":{"@type":"Answer","text":"CVE-2018-20302 was published on December 20, 2018 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."}}]}
NIST deprecates RSA-2048 from 2030. Find every one of them before attackers do.
💧
💧 Hex
Not in CISA KEV
MEDIUM severity

CVE-2018-20302 — xain

MEDIUM

CVE-2018-20302 is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in xain. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for xain — see the affected versions and patch details below.

Cross-site Scripting in xain

Also known asGHSA-5chx-gg25-v37m
Published
Updated
Affected
1 pkg
Patched
1 / 1
Exploits
1 known
Exploitation data as of Nov 3, 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 CVEs59th percentile — riskier than 59% of all scored CVEsHighest risk
0.00%0.46%0.91%1.37%0.2%0.9%May 26Sep 26Nov 26

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
💧xain

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

Description

XSS is possible via the use of the order query parameter. An example request would look like:

http://host/ressources?order=%27><script>alert(1);</script>

Affected Packages

1 total 1 fixed
EcosystemPackageVulnerable rangeFix
💧Hexxainall versions0.6.2mix deps.update xain

Affected Products

1 product · 1 configurations
Application
xainemetrotel
< 0.6.2
range
Exploits & PoCs
1

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

An XSS issue was discovered in Steve Pallen Xain before 0.6.2 via the or…

github.comNVDJan 2019

Detection & mitigation playbook

Open-source dependency

  1. Detect

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

  2. Fix

    Update xain to 0.6.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2018-20302 is resolved across your whole dependency graph.

  3. 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

XSS is possible via the use of the order query parameter. An example request would look like: ``` http://host/ressources?order=%27><script>alert(1);</script> ```
O3 Security · Impact-Aware SCA

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Find it across Hex, including transitive dependencies.

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CVE-2018-20302: xain XSS — Fixed in 0.6.2