Apache Guacamole 1.2.0 and earlier do not consistently restrict access to connection history based on user visibility.

published 2021-01-19 5 y ago modified 2026-06-17 4 mo ago also BIT-guacamole-2020-11997 , BIT-guacamole-server-2020-11997 , EUVD-2020-4314

cvss: 4.3; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.3%; EPSS 1.3% chance of exploitation in 30 days, percentile 69%
public exploits: 0; none known

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.

Patch / fix

fixed in 2

bitnami guacamole 1.2.0
bitnami guacamole-server 1.2.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2020-11997 updated 2025-11-21 cvss 4.3

guacamole-server: inconsistent history access restriction may lead to IP adress disclosure

Red Hat All currently supported Red Hat products
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

1.26% chance of exploitation in the next 30 days, higher than 69% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
NVD	3.1	4.3	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
NVD	2.0	4.0	AV:N/AC:L/Au:S/C:P/I:N/A:N
OSV	3.1	4.3	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

Affected packages

ecosystem	package	affected	fixed in
bitnami	guacamole	<1.2.0	1.2.0
bitnami	guacamole-server	<1.2.0	1.2.0

Affected products

n/a Apache Guacamole

Classification

Weakness

CWE-276 Incorrect Default Permissions

References

lists.apache.org /thread.html/r1a9ae9d1608c9f846875c4191cd738f95543d1be06b52dc1320e8117%40%3Cannounce.guacamole.apache.org%3E
mailing-list, vendor-advisory, web

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary