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CVE-2026-126069 Action View: Possible XSS vulnerability in Action View tag helpers

4.7 mediumEPSS 0.2%Fix available

Medium (4.7) in rails rails. EPSS 0.2% estimated probability of exploitation activity in the next 30 days. Fixed in actionview 8.0.5.2, 8.1.4.1.

On this page
Action View is a framework for handling view template lookup and rendering and provides view helpers for building HTML. Prior to 8.1.4.1 and 8.0.5.2, the fix for CVE-2026-33168 skips blank HTML attribute names in Action View tag helpers, but it tests the name before converting it to a string. A Symbol name made only of whitespace, such as :" ", is not blank, because Symbol#blank? is Symbol#empty?, so it reaches the attribute escaping, which emits an attribute with no name and produces malformed HTML. The asset tag helpers, such as image_tag, video_tag and audio_tag, symbolize their options, so a whitespace String name passed to them takes the same path. A carefully crafted attribute value could then be misinterpreted by the browser as a separate attribute name, possibly leading to XSS. Applications that allow users to specify custom HTML attribute names are affected. This issue is fixed in versions 8.1.4.1 and 8.0.5.2.

Severity

CVSS 3.1

4.7 medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N
EPSS
0.2% estimated probability of exploitation activity in the next 30 days; 15th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
CISA's assessment (SSVC)
Exploitation: none · Automatable: no · Technical impact: partial, assessed 2026-11-14. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
CWE
CWE-79 Improper Neutralization of Input During Web Page Generation (Cross-site Scripting)
OWASP Top 10
A05:2025 Injection
Published
Modified
Assigned by
GitHub_M (CNA)
NVD analysis
Awaiting analysis
Record from
the NVD, synced

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Affected

Versions

From the CNA's record in the CVE List.

ProductAffected
rails>= 8.1, < 8.1.4.1
rails< 8.0.5.2

Fix and patched versions

  • actionview (RubyGems): fixed in 8.1.4.1, 8.0.5.2

Packages (OSV)

AdvisoryEcosystemPackageAffectedFixed in
GHSA-68p9-83h6-5wpjRubyGemsactionview>=8.1.0.beta1 <8.1.4.18.1.4.1
GHSA-68p9-83h6-5wpjRubyGemsactionview<8.0.5.28.0.5.2

Linux distributions

DistributionReleasePackageFixed inAdvisory
Debian12, 13, 14railsno fix listedDEBIAN-CVE-2026-126069
Ubuntu24.04:LTS, 26.04:LTS, 26.10 and 4 morerailsno fix listedUBUNTU-CVE-2026-126069

From the distributions' data via OSV.dev: the Debian Security Tracker; Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Debian · Ubuntu.

Attack patterns (CAPEC)

  • CAPEC-63 Cross-Site Scripting (XSS) Likelihood: High · Severity: Very High
  • CAPEC-85 AJAX Footprinting Likelihood: High · Severity: Low
  • CAPEC-209 XSS Using MIME Type Mismatch Severity: Medium
  • CAPEC-588 DOM-Based XSS Likelihood: High · Severity: Very High
  • CAPEC-591 Reflected XSS Likelihood: High · Severity: Very High
  • CAPEC-592 Stored XSS Likelihood: High · Severity: Very High

The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.

References

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