CVE-2020-3273Network attack vector

Controller reload via incomplete GAS frame validation

Published Apr 15, 2020 · Updated Nov 15, 2024

Denial of service in Cisco WLC Software allows remote attackers to reload affected controllers via crafted 802.11 GAS frames. The GAS frame processing function incompletely validates untrusted GAS frames before handling them, allowing malformed payloads to force a controller reload. The target must have HotSpot2.0 enabled on at least one WLAN, and the frame must arrive over the air through an access point or within a CAPWAP packet over Layer 3.

CVSS severity8.6
High
EPSS probability1.27%
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 WLC Software allows remote attackers to reload affected controllers via crafted 802.11 GAS frames. The GAS frame processing function incompletely validates untrusted GAS frames before handling them, allowing malformed payloads to force a controller reload. The target must have HotSpot2.0 enabled on at least one WLAN, and the frame must arrive over the air through an access point or within a CAPWAP packet over Layer 3.

The record

CVE
CVE-2020-3273
Published
Apr 15, 2020
Updated
Nov 15, 2024
Vendor
ClamAV
Product
Cisco Wireless LAN Controller (WLC)
Classifications
CWE-119, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 15, 2020CVE publishedPublication date reported by the CVE source.
  2. Nov 15, 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?

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  1. Affected versionversion=n/a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ClamAV · Cisco Wireless LAN Controller (WLC)version=n/a

Published CVSS scores

8.6Cisco Systems, Inc.CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:X/RL:X/RC:X
5.0NIST NVDAV:N/AC:L/Au:N/C:N/I:N/A:P
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-119Improper Restriction of Operations within the Bounds of a Memory Buffer
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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