Vulnerability Description
An issue was discovered in urllib3 before 1.26.5. When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Python | Urllib3 | >= 1.25.4, < 1.26.5 |
| Fedoraproject | Fedora | 33 |
| Oracle | Enterprise Manager Ops Center | 12.4.0.0 |
| Oracle | Instantis Enterprisetrack | 17.1 |
| Oracle | Zfs Storage Appliance Kit | 8.8 |
Related Weaknesses (CWE)
References
- https://github.com/advisories/GHSA-q2q7-5pp4-w6pgThird Party Advisory
- https://github.com/urllib3/urllib3/commit/2d4a3fee6de2fa45eb82169361918f759269b4PatchThird Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://security.gentoo.org/glsa/202107-36Third Party Advisory
- https://www.oracle.com/security-alerts/cpuoct2021.htmlPatchThird Party Advisory
- https://github.com/advisories/GHSA-q2q7-5pp4-w6pgThird Party Advisory
- https://github.com/urllib3/urllib3/commit/2d4a3fee6de2fa45eb82169361918f759269b4PatchThird Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro
- https://security.gentoo.org/glsa/202107-36Third Party Advisory
- https://www.oracle.com/security-alerts/cpuoct2021.htmlPatchThird Party Advisory
FAQ
What is CVE-2021-33503?
CVE-2021-33503 is a vulnerability with a CVSS score of 7.5 (HIGH). An issue was discovered in urllib3 before 1.26.5. When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking,...
How severe is CVE-2021-33503?
CVE-2021-33503 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2021-33503?
Check the references section above for vendor advisories and patch information. Affected products include: Python Urllib3, Fedoraproject Fedora, Oracle Enterprise Manager Ops Center, Oracle Instantis Enterprisetrack, Oracle Zfs Storage Appliance Kit.