No exploitation reportedFix available

CVE-2020-11997

Q: Is CVE-2020-11997 actively exploited?

Active exploitation of CVE-2020-11997 has not been confirmed. Its EPSS score was 1.3% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

Q: What is the CVSS score for CVE-2020-11997?

CVE-2020-11997 has a CVSS v3 base score of 4.3 (MEDIUM severity), with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N.

No exploitation reported by the sources we read.

Published2021-01-19
WeaknessCWE-276

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

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.

Timeline

dates in UTC

2021-01-1922:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2020-11997?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2020-11997?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD · OSV

Apache guacamole

Branch	Affected	Fixed in	Source
1.2	≤ 1.2.0	no fix published	NVD

guacamole

Branch	Affected	Fixed in	Source
1.2	< 1.2.0	1.2.0	OSV

guacamole-server

Branch	Affected	Fixed in	Source
1.2	< 1.2.0	1.2.0	OSV

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

Advisories and patches

lists.apache.orgVendor Advisory

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

NVDCVSS 3.14.3read 2026-10-23
NVDCVSS 2.04read 2026-10-23
NVDweakness (CWE)CWE-276read 2026-10-23
FIRST EPSSEPSS score1.3 %2026-10-23
OSVaffected packages—

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Published: 2021-01-19
Last Modified: 2026-06-17
NVD status: Modified

Frequently asked questions

What is CVE-2020-11997?

Is CVE-2020-11997 actively exploited?

Active exploitation of CVE-2020-11997 has not been confirmed. Its EPSS score was 1.3% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2020-11997?

CVE-2020-11997 has a CVSS v3 base score of 4.3 (MEDIUM severity), with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N.

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