How severe is CVE-2022-20813?

CVE-2022-20813 has a CVSS 3.x base score of 9.0, rated critical severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability low.

Is CVE-2022-20813 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-20813?

CVE-2022-20813 primarily affects Cisco Expressway. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2022-20813?

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

When was CVE-2022-20813 published?

CVE-2022-20813 was published on 2022-07-06 and last updated on 2026-06-17.

CVE-2022-20813

CVE-2022-20813 is a critical-severity vulnerability in Cisco Expressway with a CVSS 3.x base score of 9.0. 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-295.

Key facts

Severity: Critical (CVSS 3.x base score 9.0)
CVSS v2: 4.3
EPSS exploit prediction: 1% (59th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Cisco Expressway
Published: 2022-07-06
Last modified: 2026-06-17

Description

Multiple vulnerabilities in the API and in the web-based management interface of Cisco Expressway Series and Cisco TelePresence Video Communication Server (VCS) could allow a remote attacker to overwrite arbitrary files or conduct null byte poisoning attacks on an affected device. Note: Cisco Expressway Series refers to the Expressway Control (Expressway-C) device and the Expressway Edge (Expressway-E) device. For more information about these vulnerabilities, see the Details section of this advisory.

Frequently asked questions

What is CVE-2022-20813?: Multiple vulnerabilities in the API and in the web-based management interface of Cisco Expressway Series and Cisco TelePresence Video Communication Server (VCS) could allow a remote attacker to overwrite arbitrary files or conduct null byte poisoning attacks on an affected device. Note: Cisco Expressway Series refers to the Expressway Control (Expressway-C) device and the Expressway Edge (Expressway-E) device. For more information about these vulnerabilities, see the Details section of this advisory.
How severe is CVE-2022-20813?: CVE-2022-20813 has a CVSS 3.x base score of 9.0, rated critical severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability low.
Is CVE-2022-20813 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-20813?: CVE-2022-20813 primarily affects Cisco Expressway. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2022-20813?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2022-20813 published?: CVE-2022-20813 was published on 2022-07-06 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-expressway-overwrite-3buqW8LH

Affected products (2)

cpe:2.3:a:cisco:expressway:*:*:*:*:*:*:*:*
cpe:2.3:a:cisco:telepresence_video_communication_server:*:*:*:*:*:*:*:*

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