How severe is CVE-2020-11997?

CVE-2020-11997 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2020-11997 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-11997?

CVE-2020-11997 affects Apache Guacamole. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-11997?

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

When was CVE-2020-11997 published?

CVE-2020-11997 was published on 2021-01-19 and last updated on 2026-06-17.

CVE-2020-11997

CVE-2020-11997 is a medium-severity vulnerability in Apache Guacamole with a CVSS 3.x base score of 4.3. 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-276.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
CVSS v2: 4.0
EPSS exploit prediction: 1% (66th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-276
Affected product: Apache Guacamole
Published: 2021-01-19
Last modified: 2026-06-17

Description

Apache Guacamole 1.2.0 and earlier do not consistently restrict access to connection history based on user visibility. If multiple users share access to the same connection, those users may be able to see which other users have accessed that connection, as well as the IP addresses from which that connection was accessed, even if those users do not otherwise have permission to see other users.

Frequently asked questions

What is CVE-2020-11997?: Apache Guacamole 1.2.0 and earlier do not consistently restrict access to connection history based on user visibility. If multiple users share access to the same connection, those users may be able to see which other users have accessed that connection, as well as the IP addresses from which that connection was accessed, even if those users do not otherwise have permission to see other users.
How severe is CVE-2020-11997?: CVE-2020-11997 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2020-11997 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-11997?: CVE-2020-11997 affects Apache Guacamole. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-11997?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-11997 published?: CVE-2020-11997 was published on 2021-01-19 and last updated on 2026-06-17.

References

https://lists.apache.org/thread.html/r1a9ae9d1608c9f846875c4191cd738f95543d1be06b52dc1320e8117%40%3Cannounce.guacamole.apache.org%3E

Affected products (1)

cpe:2.3:a:apache:guacamole:*:*:*:*:*:*:*:*

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