CVE-2020-9497
If a userconnects to a malicious or compromised RDP server, specially-craftedPDUs could result in disclosure of information within the memory ofthe guacd process handling the connection.
Does this matter?
Lower severity and a low EPSS score (0.79%). Track it; it rarely justifies an emergency change on its own.
Description
Apache Guacamole 1.1.0 and older do not properly validate datareceived from RDP servers via static virtual channels. If a userconnects to a malicious or compromised RDP server, specially-craftedPDUs could result in disclosure of information within the memory ofthe guacd process handling the connection.
- CVSS 3.1
- 4.4 MEDIUMCVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:N/A:N
- EPSS
- 0.79% probability · 56th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-20
- Affected
- apache/guacamole · fedoraproject/fedora · debian/debian linux
- Source
- security@apache.org
EPSS 0.8% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44525Third Party Advisory
- https://lists.apache.org/thread.html/r066543f0565e97b27c0dfe27e93e8a387b99e1e35764000224ed96e7%40%3Cuser.guacamole.apache.org%3E
- https://lists.apache.org/thread.html/r1125f3044a0946d1e7e6f125a6170b58d413ebd4a95157e4608041c7%40%3Cannounce.apache.org%3E
- https://lists.apache.org/thread.html/r181b1d5b1acb31cfa69f41b2c86ed3a2cb0b5bc09c2cbd31e9e7c847%40%3Cuser.guacamole.apache.org%3E
- https://lists.apache.org/thread.html/r3f071de70ea1facd3601e0fa894e6cadc960627ee7199437b5a56f7f%40%3Cannounce.apache.org%3E
- https://lists.apache.org/thread.html/r65f75d3d65d1af68141f42071ebb27dda24af3e45570e593c1dbd81f%40%3Cannounce.guacamole.apache.org%3EMailing List, Vendor Advisory
- https://lists.apache.org/thread.html/r90890afea72a9571d666820b2fe5942a0a5f86be406fa31da3dd0922%40%3Cannounce.apache.org%3E
- https://lists.debian.org/debian-lts-announce/2020/11/msg00010.htmlMailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TVV5K2X4EXSAVUUL7IJ3MUJ3ADWMVSBM/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WNS7UHBOFV6JHWH5XOEZTE3BREGRSSQ3/
- https://research.checkpoint.com/2020/apache-guacamole-rce/Third Party Advisory
- https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44525Third Party Advisory
- https://lists.apache.org/thread.html/r066543f0565e97b27c0dfe27e93e8a387b99e1e35764000224ed96e7%40%3Cuser.guacamole.apache.org%3E
- https://lists.apache.org/thread.html/r1125f3044a0946d1e7e6f125a6170b58d413ebd4a95157e4608041c7%40%3Cannounce.apache.org%3E
- https://lists.apache.org/thread.html/r181b1d5b1acb31cfa69f41b2c86ed3a2cb0b5bc09c2cbd31e9e7c847%40%3Cuser.guacamole.apache.org%3E
- https://lists.apache.org/thread.html/r3f071de70ea1facd3601e0fa894e6cadc960627ee7199437b5a56f7f%40%3Cannounce.apache.org%3E
- https://lists.apache.org/thread.html/r65f75d3d65d1af68141f42071ebb27dda24af3e45570e593c1dbd81f%40%3Cannounce.guacamole.apache.org%3EMailing List, Vendor Advisory
- https://lists.apache.org/thread.html/r90890afea72a9571d666820b2fe5942a0a5f86be406fa31da3dd0922%40%3Cannounce.apache.org%3E
- https://lists.debian.org/debian-lts-announce/2020/11/msg00010.htmlMailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TVV5K2X4EXSAVUUL7IJ3MUJ3ADWMVSBM/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WNS7UHBOFV6JHWH5XOEZTE3BREGRSSQ3/
- https://research.checkpoint.com/2020/apache-guacamole-rce/Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.