How severe is CVE-2020-27604?

CVE-2020-27604 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2020-27604 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-27604?

CVE-2020-27604 affects Bigbluebutton. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-27604?

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

When was CVE-2020-27604 published?

CVE-2020-27604 was published on 2020-10-21 and last updated on 2026-06-17.

CVE-2020-27604

CVE-2020-27604 is a medium-severity vulnerability in Bigbluebutton with a CVSS 3.x base score of 6.5. 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-116.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.0
EPSS exploit prediction: 1% (63rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-116
Affected product: Bigbluebutton
Published: 2020-10-21
Last modified: 2026-06-17

Description

BigBlueButton before 2.3 does not implement LibreOffice sandboxing. This might make it easier for remote authenticated users to read the API shared secret in the bigbluebutton.properties file. With the API shared secret, an attacker can (for example) use api/join to join an arbitrary meeting regardless of its guestPolicy setting.

Frequently asked questions

What is CVE-2020-27604?: BigBlueButton before 2.3 does not implement LibreOffice sandboxing. This might make it easier for remote authenticated users to read the API shared secret in the bigbluebutton.properties file. With the API shared secret, an attacker can (for example) use api/join to join an arbitrary meeting regardless of its guestPolicy setting.
How severe is CVE-2020-27604?: CVE-2020-27604 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2020-27604 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-27604?: CVE-2020-27604 affects Bigbluebutton. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-27604?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-27604 published?: CVE-2020-27604 was published on 2020-10-21 and last updated on 2026-06-17.

References

Affected products (1)

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

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