CVE-2020-9498: apache guacamole Out-of-bounds Write
Vulnerability summary
CVE-2020-9498 is a medium (CVSS 6.7) Out-of-bounds Write vulnerability in apache guacamole. EPSS estimates a 0.74% chance of exploitation in the next 30 days, higher than 53.7% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 2Timeline
- 02-07-2020PublishedVulnerability first disclosed.
- 04-08-2024Last modifiedVulnerability information updated.
Description
Apache Guacamole 1.1.0 and older may mishandle pointers involved inprocessing data received via RDP static virtual channels. If a userconnects to a malicious or compromised RDP server, a series ofspecially-crafted PDUs could result in memory corruption, possiblyallowing arbitrary code to be executed with the privileges of therunning guacd process.
CVSS metrics
4 scores · 3 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated6.7MediumCVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated6.7MediumCVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.74%
Chance of exploitation in the next 30 days
Percentile
54%
Versus all other CVEs
30-day change
0.00 pp
From 0.74% on 18-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Debian2 products
- guacamole-server< 1.3.0-1
- debian_linuxEOL9.0
Apache1 product
- guacamole≤ 1.1.0
Fedoraproject1 product
- fedoraEOL32 | 33
Ubuntu1 product
- guacamole-clientAll versions (No fix recorded)
4 vendors · 5 products
References
13 links- kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44525X Refsource CONFIRMThird Party Advisory
lists.debian.org/debian-lts-announce/2020/11/msg00010.htmlMailing ListX Refsource MLISTThird Party Advisory