How severe is CVE-2020-9497?

CVE-2020-9497 has a CVSS 3.x base score of 4.4, rated medium severity. It is exploitable over local access with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2020-9497 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-2020-9497?

CVE-2020-9497 primarily affects Apache Guacamole. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-9497?

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

When was CVE-2020-9497 published?

CVE-2020-9497 was published on 2020-07-02 and last updated on 2026-06-17.

CVE-2020-9497

CVE-2020-9497 is a medium-severity vulnerability in Apache Guacamole with a CVSS 3.x base score of 4.4. 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 4.4)
CVSS v2: 1.2
EPSS exploit prediction: 1% (52nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Apache Guacamole
Published: 2020-07-02
Last modified: 2026-06-17

Description

Apache Guacamole 1.1.0 and older do not properly validate datareceived from RDP servers via static virtual channels. If a userconnects to a malicious or compromised RDP server, specially-craftedPDUs could result in disclosure of information within the memory ofthe guacd process handling the connection.

Frequently asked questions

What is CVE-2020-9497?: Apache Guacamole 1.1.0 and older do not properly validate datareceived from RDP servers via static virtual channels. If a userconnects to a malicious or compromised RDP server, specially-craftedPDUs could result in disclosure of information within the memory ofthe guacd process handling the connection.
How severe is CVE-2020-9497?: CVE-2020-9497 has a CVSS 3.x base score of 4.4, rated medium severity. It is exploitable over local access with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2020-9497 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-2020-9497?: CVE-2020-9497 primarily affects Apache Guacamole. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-9497?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-9497 published?: CVE-2020-9497 was published on 2020-07-02 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:apache:guacamole:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

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