Critical Alert 1 Active Exploit Detected Today

CVE-2026-104286 — Fortinet FortiMail Path Traversal Vulnerability →
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October 2, 2026

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CVE-2026-39821NVD

Vulnerability Summary

The ToASCII and ToUnicode functions incorrectly accept Punycode-encoded labels that decode to an ASCII-only label. For example, ToUnicode("xn--example-.com") incorrectly returns the name "example.com" rather than an error. This behavior can lead to privilege escalation in programs using the idna package. For example, a program which performs privilege checks on the ASCII hostname may reject "example.com" but permit "xn--example-.com". If that program subsequently converts the ASCII hostname to Unicode, it will inadvertently permits access to the Unicode name "example.com".
Severity Level
CRITICAL(9.6)
Published Date
May 22, 2026
Last Modified
Sep 11, 2026
Exploitation Status
No confirmed exploitation yet
EPSS Score (30-Day)
0.69%Probability
Root Weakness (CWE)
N/A
CVSS v3.1 Base Metrics — Score 9.6 (CRITICAL)
Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredLow
User InteractionNone
ScopeChanged
ConfidentialityHigh
IntegrityHigh
AvailabilityNone

Affected & Patched Versions

Affected Versions
  • Golang Net < 0.55.0
Patched Versions
  • Golang Net 0.55.0
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🚨All New CVEs — Be the first to know.
📈EPSS Spike Alerts — Catch rising risk before it peaks.
🎯Custom EPSS/CVSS — Filter noise, focus on risk.
🛡️Exploit Intel — A 2nd confirmed-exploit signal beyond KEV.
🐙GitHub Issues — Auto-tracked, no duplicates.
📬Weekly Digest — One clean summary, not inbox spam.
🏷️Watchlist Groups — Tag alerts by team (Infra/AppSec/SOC).
💬Webhooks — Slack & Teams integration.
🔀Smart Routing — Critical alerts to one channel, rest to another.
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External References