CVE-2026-20233: A vulnerability in the web-based user interface of Cisco Webex Meetings could have allowed an unauthenticated,

Routine

MEDIUM 6.1DOWNGRADE

CVE-2026-20233 is a medium-severity flaw (CVSS 6.1) affecting webex meetings. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

A vulnerability in the web-based user interface of Cisco Webex Meetings could have allowed an unauthenticated, remote attacker to conduct a cross-site scripting (XSS) attack. Cisco has addressed this vulnerability in the Webex Meetings service, and no customer action is needed. This vulnerability existed because of insufficient validation of user input. Prior to this vulnerability being addressed, an attacker could have exploited this vulnerab

Why this priority

No elevated risk signals yet

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	6.1 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	0.2% (top 92%)
CISA exploited list	No
Weakness	CWE-79
Published	2026-06-03
Last modified	2026-07-22

Publisher (CNA): Cisco Systems, Inc. · Vendor: cisco

Last updated 2026-07-22 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-06-03 18:16 UTCPublished CVE record published
2026-07-22 19:10 UTCUpdated Record last modified

cisco webex meetings DOWNGRADE

Affected: 39.6.0 · 39.7.0 · 39.7.4 · 39.7.7 · 39.8.0 · 39.8.2 · 39.8.3 · 39.8.4

Fixed in: no fixed release known

Safe to downgrade to: a release before 39.6.0

1. Check installed version

apt-cache policy webex-meetings || rpm -q webex-meetings || webex-meetings --version

2. No fixed release: DOWNGRADE to a release before 39.6.0 (Debian / Ubuntu)

apt-cache madison webex-meetings sudo apt install webex-meetings=<VERSION_BEFORE_39.6.0> sudo apt-mark hold webex-meetings

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list webex-meetings sudo dnf downgrade webex-meetings-<VERSION_BEFORE_39.6.0> sudo dnf versionlock add webex-meetings

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · 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-2026-20233?

webex meetings: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2026-20233 being exploited?

CVE-2026-20233 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-2026-20233 affect?

CVE-2026-20233 affects webex meetings. Severity is medium (CVSS 6.1). A vulnerability in the web-based user interface of Cisco Webex Meetings could have allowed an unauthenticated, remote attacker to conduct a cross-site scripting (XSS) attack. Cisco has addressed this vulnerability in the Webex Meetings serv

How urgent is CVE-2026-20233?

Priority 23/100. No elevated risk signals yet.

Software pages

Cisco vulnerabilities · Cisco Webex vulnerabilities

References

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