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.
CVSS Details
- CVSS 3.1 Base Score: 5.7
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Oracle Solaris | — | Upgrade library/python-2/waitress-26 to version 0.8.5-11.4.0.0.1.9.0 on Solaris 11.4Upgrade library/python/waitress-26 to version 0.8.5-11.4.0.0.1.9.0 on Solaris 11.4Upgrade legacy/library/python/waitress-34 to version 1.4.3-11.4.21.0.1.69.0 on Solaris 11.4Upgrade library/python/waitress-35 to version 1.4.3-11.4.21.0.1.69.0 on Solaris 11.4Upgrade library/python/waitress to version 1.4.3-11.4.21.0.1.69.0 on Solaris 11.4Upgrade library/python-2/waitress to version 0.8.5-11.4.0.0.1.9.0 on Solaris 11.4Upgrade library/python/waitress-34 to version 1.4.3-11.4.21.0.1.69.0 on Solaris 11.4Upgrade library/python/waitress-27 to version 1.4.3-11.4.21.0.1.69.0 on Solaris 11.4Upgrade legacy/library/python/waitress-35 to version 1.4.3-11.4.21.0.1.69.0 on Solaris 11.4Upgrade library/python-2/waitress-27 to version 0.8.5-11.4.0.0.1.9.0 on Solaris 11.4 | Jan 19, 2021 | Feb 4, 2020 |
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