markdown2 >=1.0.1.18, fixed in 2.4.0, is affected by a regular expression denial of service vulnerability. If an attacker provides a malicious string, it can make markdown2 processing difficult or delayed for an extended period of time.
The product uses a regular expression with an inefficient, possibly exponential worst-case computational complexity that consumes excessive CPU cycles.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Markdown2 | Markdown2_project | 1.0.1.18 (including) | 2.4.0 (excluding) |
| Python-markdown2 | Ubuntu | groovy | * |
| Python-markdown2 | Ubuntu | hirsute | * |
| Python-markdown2 | Ubuntu | impish | * |
| Python-markdown2 | Ubuntu | kinetic | * |
| Python-markdown2 | Ubuntu | lunar | * |
| Python-markdown2 | Ubuntu | mantic | * |
| Python-markdown2 | Ubuntu | trusty | * |
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.