| Bug ID | 1162656 |
|---|---|
| Summary | VUL-1: CVE-2020-5236: python-waitress: DOS attack whena header that contains invalid characters is received |
| Classification | openSUSE |
| Product | openSUSE Distribution |
| Version | Leap 42.3 |
| Hardware | Other |
| URL | https://smash.suse.de/issue/252361/ |
| OS | Other |
| Status | NEW |
| Severity | Normal |
| Priority | P5 - None |
| Component | Security |
| Assignee | dmueller@suse.com |
| Reporter | atoptsoglou@suse.com |
| QA Contact | security-team@suse.de |
| Found By | Security Response Team |
| Blocker | --- |
CVE-2020-5236 Waitress version 1.4.2 allows a DOS attack When waitress receives a header that contains invalid characters. When a header like "Bad-header: xxxxxxxxxxxxxxx\x10" is received, it will cause the regular expression engine to catastrophically backtrack causing the process to use 100% CPU time and blocking any other interactions. This allows an attacker to send a single request with an invalid header and take the service offline. This issue was introduced in version 1.4.2 when the regular expression was updated to attempt to match the behaviour required by errata associated with RFC7230. The regular expression that is used to validate incoming headers has been updated in version 1.4.3, it is recommended that people upgrade to the new version of Waitress as soon as possible. References: http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2020-5236 https://github.com/Pylons/waitress/security/advisories/GHSA-73m2-3pwg-5fgc https://github.com/Pylons/waitress/commit/6e46f9e3f014d64dd7d1e258eaf626e39870ee1f http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-5236