How severe is CVE-2022-20920?

CVE-2022-20920 has a CVSS 3.x base score of 7.7, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2022-20920 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-20920?

CVE-2022-20920 primarily affects Cisco Ios. In total, 1596 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2022-20920?

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-2022-20920 published?

CVE-2022-20920 was published on 2022-10-10 and last updated on 2026-06-17.

CVE-2022-20920

CVE-2022-20920 is a high-severity vulnerability in Cisco Ios with a CVSS 3.x base score of 7.7. 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 7.7)
EPSS exploit prediction: 1% (52nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-755
Affected product: Cisco Ios
Published: 2022-10-10
Last modified: 2026-06-17

Description

A vulnerability in the SSH implementation of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, remote attacker to cause an affected device to reload. This vulnerability is due to improper handling of resources during an exceptional situation. An attacker could exploit this vulnerability by continuously connecting to an affected device and sending specific SSH requests. A successful exploit could allow the attacker to cause the affected device to reload.

Frequently asked questions

What is CVE-2022-20920?: A vulnerability in the SSH implementation of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, remote attacker to cause an affected device to reload. This vulnerability is due to improper handling of resources during an exceptional situation. An attacker could exploit this vulnerability by continuously connecting to an affected device and sending specific SSH requests. A successful exploit could allow the attacker to cause the affected device to reload.
How severe is CVE-2022-20920?: CVE-2022-20920 has a CVSS 3.x base score of 7.7, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2022-20920 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-20920?: CVE-2022-20920 primarily affects Cisco Ios. In total, 1596 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2022-20920?: 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-2022-20920 published?: CVE-2022-20920 was published on 2022-10-10 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ssh-excpt-dos-FzOBQTnk

Affected products (1596)

cpe:2.3:o:cisco:ios:12.2\(6\)i1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(58\)ex:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(58\)ey:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(58\)ey1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(58\)ey2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(58\)ez:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(58\)se:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(58\)se1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(58\)se2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(60\)ez:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(60\)ez1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(60\)ez2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(60\)ez3:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(60\)ez4:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(60\)ez5:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(60\)ez6:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(60\)ez7:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(60\)ez8:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(60\)ez9:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(60\)ez10:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(60\)ez11:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(60\)ez12:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(60\)ez13:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(60\)ez14:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2\(60\)ez15:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2ex:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2ey:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2ez:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2i:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.2se:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.4\(22\)md:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.4\(22\)md1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.4\(22\)md2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.4\(22\)mda:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.4\(22\)mda1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.4\(22\)mda2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.4\(22\)mda3:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.4\(22\)mda4:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.4\(22\)mda5:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios:12.4\(22\)mda6:*:*:*:*:*:*:*

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