---
id: CVE-2026-54521
title: >-
  FairEmail is a fully featured, open source, privacy-friendly email app for
  Android
summary: >-
  FairEmail is a fully featured, open source, privacy-friendly email app for
  Android. Prior to 1.2319, the ActivityAMP AMP message renderer in
  app/src/main/java/eu/faircode/email/ActivityAMP.java enables JavaScript in its
  WebView but incom…
severity: medium
cvss: 6.1
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N'
cwe:
  - CWE-79
vendor: M66B
product: FairEmail
affected:
  - FairEmail < 1.2319
published: '2026-09-17'
updated: '2026-09-23'
sourceUpdated: '2026-09-23T18:12:04.247'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-54521'
references:
  - url: >-
      https://github.com/M66B/FairEmail/commit/fb37bbfabf5e75d08f0cfa6ce9b84469d62a20a0
    label: security-advisories@github.com
  - url: 'https://github.com/M66B/FairEmail/releases/tag/1.2319'
    label: security-advisories@github.com
  - url: 'https://github.com/M66B/FairEmail/security/advisories/GHSA-r8ff-qr7g-pvw6'
    label: security-advisories@github.com
tags:
  - nvd
  - cve.org
epss: 0.00327
epssPercentile: 0.23038
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-18T20:08:04.050901Z'
ingestedAt: '2026-09-17T20:28:02.781Z'
---

## Overview

FairEmail is a fully featured, open source, privacy-friendly email app for Android. Prior to 1.2319, the ActivityAMP AMP message renderer in app/src/main/java/eu/faircode/email/ActivityAMP.java enables JavaScript in its WebView but incompletely sanitizes untrusted message HTML. For non-allowlisted hosts, script.removeAttr("src") leaves inline script elements in the document and does not reject event-handler attributes or javascript: URLs on other elements. A crafted AMP email can execute arbitrary JavaScript when a recipient opens the message and enables the AMP toggle. The script can read the message DOM, exfiltrate message data, and display phishing overlays within the message-body area. Exploitation requires the recipient to enable the AMP toggle, and practical exposure is reduced because AMP email is uncommon. This issue is fixed in version 1.2319.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.