CVE-2016-6366

highpriority · act · 90OT risk · criticalKEV · exploitedEPSS 0.876 · 100 %ileexploit · functionalEURUUS

grimoire priorityP0 · Act now

Exploitable?

Yes · in the wild

CISA KEV · 3 exploits · functional

Likely / severe?

87.6% (100th) EPSS

CVSS 8.5 · high

Is it mine?

12 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

added 2022-05-24remediate by 2022-06-14

required action Apply updates per vendor instructions.

EPSS · scored 2026-10-27

Cisco Adaptive Security Appliance (ASA) SNMP Buffer Overflow Vulnerability

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.

cvss

Technical severity, 0–10. One row per scoring source.

8.8

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.08.5highAV:N/AC:M/Au:S/C:C/I:C/A:Cprimary · NVD / NIST USexploitability 6.8 · impact 10

v3.18.8highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 5.9

v2.08.5highAV:N/AC:M/Au:S/C:C/I:C/A:Csecondary · FSTEC (BDU) RU

v3.18.8highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · ENISA EU

v3.18.8highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondaryexploitability 2.8 · impact 5.9

v3.18.8highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:Hsecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: active · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-120USprimaryCWE-119US

exploits (3)

Public proof-of-concept and weaponised exploit code.

auxiliary/admin/networking/cisco_asa_extrabaconCisco ASA Authentication Bypass (EXTRABACON)functional · metasploit
EDB-40258Cisco ASA 8.x - 'EXTRABACON' Authentication BypassPoC · exploit_db
RiskSense-Ops/CVE-2016-6366Public repository for improvements to the EXTRABACON exploitPoC · poc_in_github

affected products (12)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
Cisco Systems Inc. Adaptive Security Appliance≤ 9.4.2.3fstec_bduRU
cisco adaptive security appliance software7.2.1 → 9.0.4.40nvdUScpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*
cisco adaptive security appliance software9.1.1 → 9.1.7\(9\)nvdUScpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*
cisco adaptive security appliance software9.2.0 → 9.2.4\(14\)nvdUScpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*
cisco adaptive security appliance software9.3.0 → 9.3.3\(10\)nvdUScpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*
cisco adaptive security appliance software9.4.0.115 → 9.4.3\(8\)nvdUScpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*
cisco adaptive security appliance software9.5.0 → 9.5\(3\)nvdUScpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*
cisco adaptive security appliance software9.6.0 → 9.6.1\(11\)nvdUScpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*
cisco asa 1000v cloud firewall software= 8.7.1nvdUScpe:2.3:o:cisco:asa_1000v_cloud_firewall_software:*:*:*:*:*:*:*:*
cisco asa 1000v cloud firewall software= 8.7.1.1nvdUScpe:2.3:o:cisco:asa_1000v_cloud_firewall_software:*:*:*:*:*:*:*:*
cisco pix firewall softwareall versionsnvdUScpe:2.3:o:cisco:pix_firewall_software:*:*:*:*:*:*:*:*

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu nvd NVD CVE.org MITRE

published 2016-08-18modified 2026-06-17

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+5664 more

references (25)

External citations — patches, advisories, analysis.

scry

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