How severe is CVE-2021-41767?

CVE-2021-41767 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-41767 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-41767?

CVE-2021-41767 affects Apache Guacamole. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-41767?

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

When was CVE-2021-41767 published?

CVE-2021-41767 was published on 2022-01-11 and last updated on 2026-06-17.

CVE-2021-41767

CVE-2021-41767 is a medium-severity vulnerability in Apache Guacamole with a CVSS 3.x base score of 6.5. 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-200.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.0
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-200
Affected product: Apache Guacamole
Published: 2022-01-11
Last modified: 2026-06-17

Description

Apache Guacamole 1.3.0 and older may incorrectly include a private tunnel identifier in the non-private details of some REST responses. This may allow an authenticated user who already has permission to access a particular connection to read from or interact with another user's active use of that same connection.

Frequently asked questions

What is CVE-2021-41767?: Apache Guacamole 1.3.0 and older may incorrectly include a private tunnel identifier in the non-private details of some REST responses. This may allow an authenticated user who already has permission to access a particular connection to read from or interact with another user's active use of that same connection.
How severe is CVE-2021-41767?: CVE-2021-41767 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-41767 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-41767?: CVE-2021-41767 affects Apache Guacamole. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-41767?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-41767 published?: CVE-2021-41767 was published on 2022-01-11 and last updated on 2026-06-17.

References

Affected products (1)

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

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