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Weekly Signal
Live intelligence Updated 20 Aug 2026 · 12:21 UTC

Cisco · Adaptive Security Appliance (ASA), Adaptive Security Appliance Software, Asa 1000v Cloud Firewall Software +1 more

CVE-2016-6366

Cisco Adaptive Security Appliance (ASA) SNMP Buffer Overflow Vulnerability

Recommended action

Validate affected assets and exposure now, then remediate on an accelerated schedule. Cisco Security advisory Shadow Brokers

View response plan
CVSS8.8
EPSS87.6%
KEVYes
ExploitationConfirmed exploitation
RemediationNot yet verified ↓

Assessment

Why it matters

CISA lists this vulnerability as known to be exploited; exploitation is confirmed; EPSS is 87.6%; technical severity is CVSS 8.8.

Buffer overflow in Cisco Adaptive Security Appliance (ASA) Software through 9.4.2.3 on ASA 5500, ASA 5500-X, ASA Services Module, ASA 1000V, ASAv, Firepower 9300 ASA Security Module, PIX, and FWSM devices allows remote authenticated users to execute arbitrary code via crafted IPv4 SNMP packets, aka Bug ID CSCva92151 or EXTRABACON.

Who should care

  • Teams operating Adaptive Security Appliance (ASA), Adaptive Security Appliance Software, Asa 1000v Cloud Firewall Software +1 more
  • Vulnerability and exposure management teams
  • Security operations teams monitoring exploitation activity

Response plan

What I would do

  1. Confirm whether Adaptive Security Appliance (ASA), Adaptive Security Appliance Software, Asa 1000v Cloud Firewall Software +1 more is present in the environment.
  2. Identify affected versions and establish whether vulnerable services are exposed or reachable.
  3. Cisco Security advisory Shadow Brokers
  4. Review relevant security telemetry for evidence of attempted or successful exploitation.
  5. Document the remediation decision and track it to verified completion.

Treatment intelligence

Remediation intelligence

Not yet verified

Vendor sources are listed before government and third-party guidance. Confirm product applicability and change prerequisites before deployment.

Verification noteAutomated link verification has not completed for this guidance yet.

Advisory

Required Action

Technical details

CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE
CWE-119
Affected versions
Cisco Adaptive Security Appliance (ASA); Cisco Adaptive Security Appliance Software (Start Including 7.2.1, End Excluding 9.0.4.40 | Start Including 9.1.1, End Excluding 9.1.7\(9\) | Start Including 9.2.0, End Excluding 9.2.4\(14\) | Start Including 9.3.0, End Excluding 9.3.3\(10\)); Cisco Asa 1000v Cloud Firewall Software (Version 8.7.1 | Version 8.7.1.1); Cisco Pix Firewall Software (Version -)
Fixed versions
Cisco Adaptive Security Appliance Software (Fixed from 9.0.4.40, 9.1.7\(9\), 9.2.4\(14\), 9.3.3\(10\), 9.4.3\(8\), 9.6.1\(11\))
Published
18 August 2016
Attack vector
Network
Privileges required
Low
User interaction
None

Signal timeline

  1. CVE published
  2. Added to CISA KEV
  3. Latest EPSS score: 87.6%
  4. Signal calculated at 83

External references

Live public intelligence This assessment combines public-source evidence. Validate the affected product, version and exposure against your own environment before making a risk decision.