GHSA-7xx3-m584-x994
A poorly-behaved client could use keepalive requests to monopolize Puma's reactor and create a denial of service attack
Packages
Details
As written in the advisory (Markdown source, shown as plain text).
## Keepalive thread overload/DoS
### Impact
A poorly-behaved client could use keepalive requests to monopolize Puma's reactor and create a denial of service attack.
If more keepalive connections to Puma are opened than there are threads available, additional connections will wait permanently if the attacker sends requests frequently enough.
### Patches
This vulnerability is patched in Puma 4.3.1 and 3.12.2.
### Workarounds
Reverse proxies in front of Puma could be configured to always allow less than X keepalive connections to a Puma cluster or process, where X is the number of threads configured in Puma's thread pool.
### For more information
If you have any questions or comments about this advisory:
* Open an issue at [puma](github.com/puma/puma).
References
External links from the advisory. They lead to third-party sites.
- https://github.com/puma/puma/security/advisories/GHSA-7xx3-m584-x994
- https://nvd.nist.gov/vuln/detail/CVE-2019-16770
- https://github.com/advisories/GHSA-7xx3-m584-x994
- https://github.com/rubysec/ruby-advisory-db/blob/master/gems/puma/CVE-2019-16770.yml
- https://lists.debian.org/debian-lts-announce/2022/05/msg00034.html