Improper input validation in Bigbluebutton
CVE-2022-29169
BigBlueButton is an open source web conferencing system. Versions starting with 2.2 and prior to 2.3.19, 2.4.7, and 2.5.0-beta.2 are vulnerable to regular expression denial of service (ReDoS) attacks. By using specific a RegularExpression, an attacker can cause denial of service for the bbb-html5 service. The useragent library performs checking of device by parsing the input of User-Agent header and lets it go through lookupUserAgent() (alias of useragent.lookup() ). This function handles input by regexing and attackers can abuse that by providing some ReDos payload using `SmartWatch`. The maintainers removed `htmlclient/useragent` from versions 2.3.19, 2.4.7, and 2.5.0-beta.2. As a workaround, disable NginX forwarding the requests to the handler according to the directions in the GitHub Security Advisory.
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
EPSS: 0.015 (71.3th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
Affected products
- Bigbluebutton — versions >= 2.4.0, < 2.4.7, >= 2.2, < 2.3.19, 2.5
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Patch, Third Party Advisory, Mitigation)
- security-advisories@github.com (Patch, Third Party Advisory, x_refsource_MISC)
- security-advisories@github.com (Patch, Third Party Advisory, x_refsource_MISC)
Frequently asked questions
- What is CVE-2022-29169?
- CVE-2022-29169 is a high-severity vulnerability in Bigbluebutton, classified under Improper Input Validation. CVSS score: 7.5/10. Published 2022-06-01.
- How severe is CVE-2022-29169?
- High severity. CVSS v3 base score is 7.5 out of 10.