How severe is CVE-2022-20678?

CVE-2022-20678 has a CVSS 3.x base score of 8.6, 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 none, and availability high.

Is CVE-2022-20678 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-20678?

CVE-2022-20678 primarily affects Cisco Ios Xe. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2022-20678?

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-2022-20678 published?

CVE-2022-20678 was published on 2022-04-15 and last updated on 2026-06-17.

CVE-2022-20678

CVE-2022-20678 is a high-severity vulnerability in Cisco Ios Xe with a CVSS 3.x base score of 8.6. 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-755.

Key facts

Severity: High (CVSS 3.x base score 8.6)
CVSS v2: 7.8
EPSS exploit prediction: 1% (56th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-755
Affected product: Cisco Ios Xe
Published: 2022-04-15
Last modified: 2026-06-17

Description

A vulnerability in the AppNav-XE feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. This vulnerability is due to the incorrect handling of certain TCP segments. An attacker could exploit this vulnerability by sending a stream of crafted TCP traffic at a high rate through an interface of an affected device. That interface would need to have AppNav interception enabled. A successful exploit could allow the attacker to cause the device to reload.

Frequently asked questions

What is CVE-2022-20678?: A vulnerability in the AppNav-XE feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. This vulnerability is due to the incorrect handling of certain TCP segments. An attacker could exploit this vulnerability by sending a stream of crafted TCP traffic at a high rate through an interface of an affected device. That interface would need to have AppNav interception enabled. A successful exploit could allow the attacker to cause the device to reload.
How severe is CVE-2022-20678?: CVE-2022-20678 has a CVSS 3.x base score of 8.6, 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 none, and availability high.
Is CVE-2022-20678 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-20678?: CVE-2022-20678 primarily affects Cisco Ios Xe. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2022-20678?: 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-2022-20678 published?: CVE-2022-20678 was published on 2022-04-15 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-appnav-xe-dos-j5MXTR4

Affected products (4)

cpe:2.3:o:cisco:ios_xe:16.9.6:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.12.4:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.12.5:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:17.3.3:*:*:*:*:*:*:*

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