Loofah is a general library for manipulating and transforming HTML/XML documents and fragments, built on top of Nokogiri. Loofah < 2.19.1 contains an inefficient regular expression that is susceptible to excessive backtracking when attempting to sanitize certain SVG attributes. This may lead to a denial of service through CPU resource consumption. This issue is patched in version 2.19.1.
Weakness
The product uses a regular expression with an inefficient, possibly exponential worst-case computational complexity that consumes excessive CPU cycles.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Loofah | Loofah_project | * | 2.19.1 (excluding) |
| Red Hat Satellite 6.13 for RHEL 8 | RedHat | satellite:el8/rubygem-loofah-0:2.19.1-1.el8sat | * |
| Ruby-loofah | Ubuntu | bionic | * |
| Ruby-loofah | Ubuntu | focal | * |
| Ruby-loofah | Ubuntu | kinetic | * |
| Ruby-loofah | Ubuntu | lunar | * |
| Ruby-loofah | Ubuntu | trusty | * |
| Ruby-loofah | Ubuntu | upstream | * |
| Ruby-loofah | Ubuntu | xenial | * |
Extended Description
Attackers can create crafted inputs that
intentionally cause the regular expression to use
excessive backtracking in a way that causes the CPU
consumption to spike.
Potential Mitigations
Related Attack Patterns
References
- https://github.com/flavorjones/loofah/security/advisories/GHSA-486f-hjj9-9vhh
- https://hackerone.com/reports/1684163
- https://lists.debian.org/debian-lts-announce/2023/09/msg00011.html
- https://github.com/flavorjones/loofah/security/advisories/GHSA-486f-hjj9-9vhh
- https://hackerone.com/reports/1684163
- https://lists.debian.org/debian-lts-announce/2023/09/msg00011.html
- https://lists.debian.org/debian-lts-announce/2024/09/msg00044.html