CVE-2022-23517

rails-html-sanitizer is responsible for sanitizing HTML fragments in Rails applications. Certain configurations of rails-html-sanitizer < 1.4.4 use 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 has been patched in version 1.4.4.

Weakness

The product uses a regular expression with an inefficient, possibly exponential worst-case computational complexity that consumes excessive CPU cycles.

Affected Software

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

• https://cwe.mitre.org/data/definitions/492.html

References

• https://github.com/rails/rails-html-sanitizer/commit/56c61c0cebd1e493e8ad7bca2a0191609a4a6979
• https://github.com/rails/rails-html-sanitizer/security/advisories/GHSA-5x79-w82f-gw8w
• https://hackerone.com/reports/1684163
• https://lists.debian.org/debian-lts-announce/2023/09/msg00012.html
• https://github.com/rails/rails-html-sanitizer/commit/56c61c0cebd1e493e8ad7bca2a0191609a4a6979
• https://github.com/rails/rails-html-sanitizer/security/advisories/GHSA-5x79-w82f-gw8w
• https://hackerone.com/reports/1684163
• https://lists.debian.org/debian-lts-announce/2023/09/msg00012.html
• https://lists.debian.org/debian-lts-announce/2024/09/msg00045.html