CVE intelligence and bounded remediation

CVE-2018-12242 — Symantec Messaging Gateway security vulnerability

Critical CVSS 9.8

The Symantec Messaging Gateway product prior to 10.6.6 may be susceptible to an authentication bypass exploit, which is a type of issue that can allow attackers to potentially circumvent security mechanisms currently in place and gain access to the system or network.

Severity
Critical
CVSS
9.8 (3.0)
Published
2018-09-19
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-287

Affected products

  • symantec / messaging_gateway

Matched remediation archetype

Authentication bypass and missing authentication

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Check exposure

  • Map every affected endpoint and protocol path, including alternate ports, legacy routes, recovery flows, service accounts, and machine-to-machine access.
  • Confirm which deployments enable the affected authentication mode and whether the interface is reachable from untrusted networks.
  • Review session, token, credential, and proxy trust configuration without attempting account takeover.

Remediate safely

  • Apply the supported fix and centralize fail-closed authentication before protected request handling.
  • Remove default or embedded credentials, rotate affected secrets and sessions, and bind authentication decisions to the intended audience and channel.
  • Add negative tests for alternate routes, malformed or absent credentials, recovery flows, and proxy-derived identity.

Authoritative sources

Complete CVE record and remediation plan

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