QID 352486

Date Published: 2021-07-21

QID 352486: Amazon Linux Security Advisory for python-urllib3: ALAS2-2021-1688

A flaw was found in python-urllib3.
When provided with a url containing many @ characters in the authority component, the authority's regular expression exhibits catastrophic backtracking.
This flaw causes a denial of service if a url is passed as a parameter or redirected via an http redirect.
The highest threat from this vulnerability is to system availability. (
( CVE-2021-33503)



Note: The preceding description block is extracted directly from the security advisory. Using automation, we have attempted to clean and format it as much as possible without introducing additional issues.

Allows unauthorized disclosure of information; allows unauthorized modification; allows disruption of service.

  • CVSS V3 rated as High - 7.5 severity.
  • CVSS V2 rated as Medium - 5 severity.
    • Solution
    Please refer to Amazon advisory: ALAS2-2021-1688 for affected packages and patching details, or update with your package manager.
    Vendor References

    CVEs related to QID 352486

    CVE-2021-33503 |
    Software Advisories
    Advisory ID Software Component Link
    ALAS2-2021-1688 Amazon Linux 2 URL Logo alas.aws.amazon.com/AL2/ALAS-2021-1688.html
    By selecting these links, you may be leaving CVEreport webspace. We have provided these links to other websites because they may have information that would be of interest to you. No inferences should be drawn on account of other sites being referenced, or not, from this page. There may be other websites that are more appropriate for your purpose. CVEreport does not necessarily endorse the views expressed, or concur with the facts presented on these sites. Further, CVEreport does not endorse any commercial products that may be mentioned on these sites. Please address comments about any linked pages to [email protected].