How severe is CVE-2020-27608?

CVE-2020-27608 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2020-27608 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-27608?

CVE-2020-27608 affects Bigbluebutton. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-27608?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2020-27608 published?

CVE-2020-27608 was published on 2020-10-21 and last updated on 2026-06-17.

CVE-2020-27608

CVE-2020-27608 is a medium-severity vulnerability in Bigbluebutton with a CVSS 3.x base score of 6.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v2: 4.3
EPSS exploit prediction: 1% (48th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Bigbluebutton
Published: 2020-10-21
Last modified: 2026-06-17

Description

In BigBlueButton before 2.2.28 (or earlier), uploaded presentations are sent to clients without a Content-Type header, which allows XSS, as demonstrated by a .png file extension for an HTML document.

Frequently asked questions

What is CVE-2020-27608?: In BigBlueButton before 2.2.28 (or earlier), uploaded presentations are sent to clients without a Content-Type header, which allows XSS, as demonstrated by a .png file extension for an HTML document.
How severe is CVE-2020-27608?: CVE-2020-27608 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2020-27608 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-27608?: CVE-2020-27608 affects Bigbluebutton. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-27608?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-27608 published?: CVE-2020-27608 was published on 2020-10-21 and last updated on 2026-06-17.

References

https://www.golem.de/news/big-blue-button-das-grosse-blaue-sicherheitsrisiko-2010-151610.html

Affected products (1)

cpe:2.3:a:bigbluebutton:bigbluebutton:*:*:*:*:*:*:*:*

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