CVE-2024-20534: A vulnerability in the web UI of Cisco Desk Phone 9800 Series, Cisco IP Phone 6800, 7800, and 8800 Series, and
22
Routine
MEDIUM 4.8MITIGATEMITIGATEMITIGATE
CVE-2024-20534 is a medium-severity flaw (CVSS 4.8) affecting desk phone 9841 with multiplatform firmware, desk phone 9851 with multiplatform firmware, desk phone 9861 with multiplatform firmware. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
A vulnerability in the web UI of Cisco Desk Phone 9800 Series, Cisco IP Phone 6800, 7800, and 8800 Series, and Cisco Video Phone 8875 with Cisco Multiplatform Firmware could allow an authenticated, remote attacker to conduct stored cross-site scripting (XSS) attacks against users.
This vulnerability exists because the web UI of an affected device does not properly validate user-supplied input. An attacker could exploit this vulnerability by in
Why this priority
No elevated risk signals yet
No fix is published yet: follow the downgrade or mitigation steps.
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
Published CVE record published
Updated Record last modified
cisco desk phone 9841 with multiplatform firmware MITIGATE
Affected: 3.1\(1\) · 3.1\(1\) sr1
Fixed in: no fixed release known
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
cisco desk phone 9851 with multiplatform firmware MITIGATE
Affected: 3.1\(1\) · 3.1\(1\) sr1
Fixed in: no fixed release known
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
cisco desk phone 9861 with multiplatform firmware MITIGATE
Affected: 3.1\(1\) · 3.1\(1\) sr1
Fixed in: no fixed release known
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
cisco desk phone 9871 with multiplatform firmware MITIGATE
Affected: 3.1\(1\) · 3.1\(1\) sr1
Fixed in: no fixed release known
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
cisco ip phone 6821 with multiplatform firmware MITIGATE
Affected: 12.0\(5\) sr1
Fixed in: no fixed release known
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
cisco ip phone 6841 with multiplatform firmware MITIGATE
Affected: 12.0\(5\) sr1
Fixed in: no fixed release known
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
Verify at the official sourceNVD · CVE Program · Report a problem with this page Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2024-20534?
desk phone 9841 with multiplatform firmware: mitigate or apply the listed mitigation; desk phone 9851 with multiplatform firmware: mitigate or apply the listed mitigation; desk phone 9861 with multiplatform firmware: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.
Is CVE-2024-20534 being exploited?
CVE-2024-20534 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2024-20534 affect?
CVE-2024-20534 affects desk phone 9841 with multiplatform firmware, desk phone 9851 with multiplatform firmware, desk phone 9861 with multiplatform firmware. Severity is medium (CVSS 4.8). A vulnerability in the web UI of Cisco Desk Phone 9800 Series, Cisco IP Phone 6800, 7800, and 8800 Series, and Cisco Video Phone 8875 with Cisco Multiplatform Firmware could allow an authenticated, remote attacker to conduct stored cross-si
CVE-2024-20533MEDIUM 4.8MITIGATEMITIGATE A vulnerability in the web UI of Cisco Desk Phone 9800 Series, Cisco IP Phone 6800, 7800, and 8800 Series, and
PatchTheCVE