How severe is CVE-2020-3444?

CVE-2020-3444 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2020-3444 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-3444?

CVE-2020-3444 affects Cisco Ios Xe. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-3444?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2020-3444 published?

CVE-2020-3444 was published on 2020-11-06 and last updated on 2026-06-17.

CVE-2020-3444

CVE-2020-3444 is a high-severity vulnerability in Cisco Ios Xe with a CVSS 3.x base score of 7.5. 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: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (71st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Ios Xe
Published: 2020-11-06
Last modified: 2026-06-17

Description

A vulnerability in the packet filtering features of Cisco SD-WAN Software could allow an unauthenticated, remote attacker to bypass L3 and L4 traffic filters. The vulnerability is due to improper traffic filtering conditions on an affected device. An attacker could exploit this vulnerability by crafting a malicious TCP packet with specific characteristics and sending it to a targeted device. A successful exploit could allow the attacker to bypass the L3 and L4 traffic filters and inject an arbitrary packet into the network.

Frequently asked questions

What is CVE-2020-3444?: A vulnerability in the packet filtering features of Cisco SD-WAN Software could allow an unauthenticated, remote attacker to bypass L3 and L4 traffic filters. The vulnerability is due to improper traffic filtering conditions on an affected device. An attacker could exploit this vulnerability by crafting a malicious TCP packet with specific characteristics and sending it to a targeted device. A successful exploit could allow the attacker to bypass the L3 and L4 traffic filters and inject an arbitrary packet into the network.
How severe is CVE-2020-3444?: CVE-2020-3444 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2020-3444 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-3444?: CVE-2020-3444 affects Cisco Ios Xe. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-3444?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-3444 published?: CVE-2020-3444 was published on 2020-11-06 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cedge-filt-bypass-Y6wZMqm4

Affected products (1)

cpe:2.3:o:cisco:ios_xe:*:*:*:*:*:*:*:*

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