Threats / Symantec / CVE-2017-6327
CVE-2017-6327
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-06-22
Symantec Messaging Gateway vulnerability
Symantec Messaging Gateway contains an unspecified vulnerability allowing remote code execution. The flaw has been exploited in the wild.
Verdict
Today item — known-exploited.
An unauthenticated attacker can execute arbitrary code on affected Symantec Messaging Gateway instances, potentially gaining system-level access and control over email infrastructure.
01
Is it exploitable?
— the evidence, ranked above the scoreReported exploitation
4 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03).
Probability (EPSS)
EPSS 0.35341 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Symantec, Symantec Messaging Gateway. Confirm exact fixed builds in the vendor advisory.
Weakness (CWE)
Mapped to CWE-20 Improper Input Validation.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution not established
No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.
03
Why it matters
— the attack path, told twice: adversary, then board1
Front door — unauthenticated access narrative 1
Attacker
I identify and exploit an input validation flaw in Symantec Messaging Gateway to inject malicious code.
Business
Email gateway security is compromised, exposing the organization's messaging infrastructure to unauthorized access.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I execute arbitrary commands on the compromised gateway server to establish persistence and escalate privileges.
Business
Attackers gain administrative control over email systems, enabling data exfiltration, message interception, and lateral network movement.
3
Lateral reach — past segmentation narrative 3
Attacker
I leverage gateway access to intercept, modify, or redirect sensitive email communications.
Business
Confidential business communications are exposed; regulatory compliance obligations are violated; customer trust is damaged.
04
What to do
— defensible action- Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05