CVE-2022-29169 json
ReDoS on endpoint html5client/useragent in BigBlueButton
published 2022-06-01 4 y ago modified 2026-06-17 4 mo ago also EUVD-2022-33571
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.6%
- EPSS 1.6% chance of exploitation in 30 days, percentile 75%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- bigbluebutton bigbluebutton 2.3.19, 2.4.7
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 18 mo ago
Exploit prediction
1.59% chance of exploitation in the next 30 days, higher than 75% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:N/A:P |
Affected products
- bigbluebutton bigbluebutton
Classification
References
-
github.com
/bigbluebutton/bigbluebutton/pull/14886
patch, third-party-advisory
-
github.com
/bigbluebutton/bigbluebutton/pull/14896
patch, third-party-advisory
-
github.com
/bigbluebutton/bigbluebutton/security/advisories/GHSA-rwrv-p665-4vwp
mitigation, patch, third-party-advisory
Sources
- CVE List CVE-2022-29169
- NVD CVE-2022-29169
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