CVE-2022-20683Network attack vector

Device crash via insufficient AVC packet verification

Published Apr 15, 2022 · Updated Nov 6, 2024

Denial of service in Cisco IOS XE Software for Catalyst 9800 controllers allows remote attackers to crash and reload affected devices. The AVC-FNF feature insufficiently verifies crafted packets sent from the wired network to a wireless client before the controller processes them. Exposure requires AVC-FNF, which is disabled by default, plus an access point using local, bridge, or FlexConnect Central Switching mode.

CVSS severity8.6
High
EPSS probability1.49%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Cisco IOS XE Software for Catalyst 9800 controllers allows remote attackers to crash and reload affected devices. The AVC-FNF feature insufficiently verifies crafted packets sent from the wired network to a wireless client before the controller processes them. Exposure requires AVC-FNF, which is disabled by default, plus an access point using local, bridge, or FlexConnect Central Switching mode.

The record

CVE
CVE-2022-20683
Published
Apr 15, 2022
Updated
Nov 6, 2024
Vendor
ClamAV
Product
Cisco IOS XE Software
Classifications
CWE-124, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 15, 2022CVE publishedPublication date reported by the CVE source.
  2. Nov 6, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=n/a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ClamAV · Cisco IOS XE Softwareversion=n/a

Published CVSS scores

8.6CiscoCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:X/RL:X/RC:X

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-124Buffer Underwrite ('Buffer Underflow')
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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