How severe is CVE-2022-20784?

CVE-2022-20784 has a CVSS 3.x base score of 5.8, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2022-20784 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-20784?

CVE-2022-20784 affects Cisco Web Security Appliance. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2022-20784?

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

When was CVE-2022-20784 published?

CVE-2022-20784 was published on 2022-04-06 and last updated on 2026-06-17.

CVE-2022-20784

CVE-2022-20784 is a medium-severity vulnerability in Cisco Web Security Appliance with a CVSS 3.x base score of 5.8. 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 5.8)
CVSS v2: 5.0
EPSS exploit prediction: 1% (55th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Web Security Appliance
Published: 2022-04-06
Last modified: 2026-06-17

Description

A vulnerability in the Web-Based Reputation Score (WBRS) engine of Cisco AsyncOS Software for Cisco Web Security Appliance (WSA) could allow an unauthenticated, remote attacker to bypass established web request policies and access blocked content on an affected device. This vulnerability is due to incorrect handling of certain character combinations inserted into a URL. An attacker could exploit this vulnerability by sending crafted URLs to be processed by an affected device. A successful exploit could allow the attacker to bypass the web proxy and access web content that has been blocked by policy.

Frequently asked questions

What is CVE-2022-20784?: A vulnerability in the Web-Based Reputation Score (WBRS) engine of Cisco AsyncOS Software for Cisco Web Security Appliance (WSA) could allow an unauthenticated, remote attacker to bypass established web request policies and access blocked content on an affected device. This vulnerability is due to incorrect handling of certain character combinations inserted into a URL. An attacker could exploit this vulnerability by sending crafted URLs to be processed by an affected device. A successful exploit could allow the attacker to bypass the web proxy and access web content that has been blocked by policy.
How severe is CVE-2022-20784?: CVE-2022-20784 has a CVSS 3.x base score of 5.8, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2022-20784 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-20784?: CVE-2022-20784 affects Cisco Web Security Appliance. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2022-20784?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2022-20784 published?: CVE-2022-20784 was published on 2022-04-06 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-swa-filter-bypass-XXXTU3X

Affected products (1)

cpe:2.3:a:cisco:web_security_appliance:*:*:*:*:*:*:*:*

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