How severe is CVE-2022-23518?

CVE-2022-23518 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-2022-23518?

CVE-2022-23518 affects the following packages: rails-html-sanitizer (RubyGems). Ecosystems affected: RubyGems.

How do I fix CVE-2022-23518?

Update rails-html-sanitizer to 1.4.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-23518 is resolved across your whole dependency graph.

How do I detect CVE-2022-23518 in my RubyGems dependencies?

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

How do I mitigate CVE-2022-23518 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-2022-23518 actively exploited in the wild?

Yes. There are 1 known exploit references for CVE-2022-23518, 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-2022-23518?

CVE-2022-23518 has an EPSS (Exploit Prediction Scoring System) score of 0.9%, placing it in the 61th 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-2022-23518?

CVE-2022-23518 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-2022-23518 published, and has it been updated?

CVE-2022-23518 was published on December 14, 2022 and was last updated on October 28, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

💎

💎 RubyGems

Not in CISA KEV

MEDIUM severity

CVE-2022-23518 — rails-html-sanitizer

MEDIUM

CVE-2022-23518 is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in rails-html-sanitizer. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for rails-html-sanitizer — see the affected versions and patch details below.

Improper neutralization of data URIs allows XSS in rails-html-sanitizer

Also known asGHSA-mcvf-2q2m-x72m

Published

Dec 14, 2022

Updated

Oct 28, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

1 known

Exploitation data as of Nov 6, 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 CVEs61th percentile — riskier than 61% 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

💎rails-html-sanitizer

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

Description

Summary

rails-html-sanitizer >= 1.0.3, < 1.4.4 is vulnerable to cross-site scripting via data URIs when used in combination with Loofah >= 2.1.0.

Mitigation

Upgrade to rails-html-sanitizer >= 1.4.4.

Severity

The maintainers have evaluated this as Medium Severity 6.1.

References

Credit

This vulnerability was independently reported by Maciej Piechota (@haqpl) and Mrinmoy Das (@goromlagche).

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
💎RubyGems	`rails-html-sanitizer`	≥ 1.0.3&&< 1.4.4	1.4.4`bundle update rails-html-sanitizer --conservative`

Affected Products

3 products · 3 configurations

debian linuxdebian

1 version

10.0

Application

loofahloofah_project

≥ 2.1.0 && < 2.19.1

range

Application

rails html sanitizersrubyonrails

≥ 1.0.3 && < 1.4.4

range

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.

rails-html-sanitizer is responsible for sanitizing HTML fragments in Rai…

github.comNVDDec 2022

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for rails-html-sanitizer, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update rails-html-sanitizer to 1.4.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-23518 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.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatModerate

Product	Fixed in	Advisory
Red Hat Satellite 6.13 for RHEL 8	`tfm-rubygem-rails-html-sanitizer-0:1.4.4-1.el8sat`	RHSA-2023:2097

Frequently Asked Questions

## Summary rails-html-sanitizer `>= 1.0.3, < 1.4.4` is vulnerable to cross-site scripting via data URIs when used in combination with Loofah `>= 2.1.0`. ## Mitigation Upgrade to rails-html-sanitizer `>= 1.4.4`. ## Severity The maintainers have evaluated this as [Medium Severity 6.1](https://www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N). ## References - [CWE - CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') (4.9)](https://cwe.mitre.org/data/definitions/79.html) - [SVG MIME Type (image/svg+xml) is misleading

O3 Security · Impact-Aware SCA

Is CVE-2022-23518 in your dependencies?

Find it across RubyGems, including transitive dependencies.

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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:3.0/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 Nuclei template or Metasploit module yet. 1 public proof-of-concept reference is listed on this page.

Timeline

Disclosed

Dec 14, 2022

First exploit

Dec 16, 2022

2 days after disclosure — rapid exploitation

Last updated

Oct 28, 2026

Identifiers

CVE-2022-23518

GHSA-mcvf-2q2m-x72m

References

Advisorygithub.com · CVE 2022 23518.json Advisorygithub.com · GHSA mcvf 2q2m x72m Advisorynvd.nist.gov · CVE 2022 23518 Reportgithub.com Webhackerone.com Weblists.debian.org · msg00012 Weblists.debian.org · msg00045 Webgithub.com Webgithub.com · CVE 2022 23518.yml Packagegithub.com · rails html sanitizer

Related vulnerabilities

This CVE is medium severity; 3 of 8 other CVEs affecting rails-html-sanitizer are rated as high or higher (top: high).

CVE-2026-73648CVE-2024-53987CVE-2024-53986CVE-2024-53988CVE-2024-53989CVE-2024-53985CVE-2022-23517CVE-2022-23519

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedOct 28, 2026

CVE-2022-23518 — rails-html-sanitizer

EPSS Exploitation Probability

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

Description

Summary

Mitigation

Severity

References

Credit

Affected Packages

Affected Products

Detection & mitigation playbook

Detect

Fix

Workarounds

Fixing This On Your OS

Frequently Asked Questions

Is CVE-2022-23518 in your dependencies?