CVE intelligence and bounded remediation

CVE-2018-0353 — Cisco Web Security Appliance security vulnerability

High CVSS 7.5

A vulnerability in traffic-monitoring functions in Cisco Web Security Appliance (WSA) could allow an unauthenticated, remote attacker to circumvent Layer 4 Traffic Monitor (L4TM) functionality and bypass security protections. The vulnerability is due to a change in the underlying operating system software that is responsible for monitoring affected traffic. An attacker could exploit this vulnerability by sending crafted IP packets to an affected device. A successful exploit could allow the attacker to pass traffic through the device, which the WSA was configured to deny. This vulnerability affects both IPv4 and IPv6 traffic. This vulnerability affects Cisco AsyncOS versions for WSA on both virtual and hardware appliances running any release of the 10.5.1, 10.5.2, or 11.0.0 WSA Software. The WSA is vulnerable if it is configured for L4TM. Cisco Bug IDs: CSCvg78875.

Severity
High
CVSS
7.5 (3.0)
Published
2018-06-07
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-254

Affected products

  • cisco / web_security_appliance / 10.5.1
  • cisco / web_security_appliance / 10.5.1-296
  • cisco / web_security_appliance / 10.5.2
  • cisco / web_security_appliance / 11.0.0
  • cisco / web_security_appliance / 11.5.0-fcs-442

Matched remediation archetype

General vulnerability remediation

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Confirm the affected component, deployment paths, reachable interfaces, and enabled features from inventories and configuration, without probing production destructively.
  • Compare the advisory's affected conditions with the repository lockfiles, build manifests, artifacts, and runtime inventory.
  • Identify data sensitivity, trust boundaries, and privilege level for every confirmed affected deployment.

Remediate safely

  • Apply a vendor-supported fix or remove the affected component or feature; record the selected change and its source in the repository.
  • Update direct and transitive dependency locks, generated artifacts, deployment manifests, and asset inventories together.
  • Add a regression test for the documented unsafe condition using inert inputs and preserve rollback instructions.

Authoritative sources

Complete CVE record and remediation plan

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