CVE-2026-104083
mediumpriority · track · 24EPSS 0.003 · 25 %ileDEEPSS · scored 2026-10-26
SmarterMail before build 9777 contains a stored mutation cross-site scripting vulnerability that allows remote attackers to inject executable script by placing payloads inside a <style> element nested within MathML foreign content (<math><mtext><mglyph>), which the custom HTML sanitizer treats as inert CDATA text but browsers reparse as live markup. Attackers can deliver a crafted calendar (iCal) message containing an <img src=x onerror=...> payload that executes automatically in the recipient's webmail session at /interface/message-iframe when the message is opened, enabling script execution and data exfiltration unconstrained by the interface's permissive Content-Security-Policy.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 1.3–6.1
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (2)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-3869SmarterTools SmarterMail: Mehrere SchwachstellenDeutsch2026-10-11csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in SmarterTools SmarterMail ausnutzen, um beliebigen Code mit SYSTEM-Rechten auszuführen, erhöhte Rechte auch weiterhin zu behalten, nachdem die Administratorrechte entzogen wurden, Cross-Site-Scripting-Angriffe zu starten, Sicherheitsmaßnahmen zu umgehen, Daten offenzulegen oder zu manipulieren sowie weitere, unspezifizierte Angriffe durchzuführen.
sources
Which sources assert this record, and when.
references (3) nvd
External citations — patches, advisories, analysis.
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