FairEmail: Cross-site scripting (XSS) in AMP message rendering (ActivityAMP)
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.1epss 0.2%
exploitation probability
0.2%top 85% of all CVEs
observed exploitation
nono source reports it
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Affected products
M66B · FairEmail