How severe is CVE-2020-3429?

CVE-2020-3429 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2020-3429 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-3429?

CVE-2020-3429 affects Cisco Ios Xe. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-3429?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2020-3429 published?

CVE-2020-3429 was published on 2020-09-24 and last updated on 2026-06-17.

CVE-2020-3429

CVE-2020-3429 is a medium-severity vulnerability in Cisco Ios Xe with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 5.7
EPSS exploit prediction: 1% (50th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Ios Xe
Published: 2020-09-24
Last modified: 2026-06-17

Description

A vulnerability in the WPA2 and WPA3 security implementation of Cisco IOS XE Wireless Controller Software for the Cisco Catalyst 9000 Family could allow an unauthenticated, adjacent attacker to cause denial of service (DoS) condition on an affected device. The vulnerability is due to incorrect packet processing during the WPA2 and WPA3 authentication handshake when configured for dot1x or pre-shared key (PSK) authentication key management (AKM) with 802.11r BSS Fast Transition (FT) enabled. An attacker could exploit this vulnerability by sending a crafted authentication packet to an affected device. A successful exploit could cause an affected device to reload, resulting in a DoS condition.

Frequently asked questions

What is CVE-2020-3429?: A vulnerability in the WPA2 and WPA3 security implementation of Cisco IOS XE Wireless Controller Software for the Cisco Catalyst 9000 Family could allow an unauthenticated, adjacent attacker to cause denial of service (DoS) condition on an affected device. The vulnerability is due to incorrect packet processing during the WPA2 and WPA3 authentication handshake when configured for dot1x or pre-shared key (PSK) authentication key management (AKM) with 802.11r BSS Fast Transition (FT) enabled. An attacker could exploit this vulnerability by sending a crafted authentication packet to an affected device. A successful exploit could cause an affected device to reload, resulting in a DoS condition.
How severe is CVE-2020-3429?: CVE-2020-3429 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2020-3429 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-3429?: CVE-2020-3429 affects Cisco Ios Xe. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-3429?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-3429 published?: CVE-2020-3429 was published on 2020-09-24 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-wpa-dos-cXshjerc

Affected products (1)

cpe:2.3:o:cisco:ios_xe:16.12.1s:*:*:*:*:*:*:*

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