Vulnerabilities
Misconfiguration
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CVE Vulnerabilities

CVE-2021-33503

Uncontrolled Resource Consumption

Published: Jun 29, 2021 | Modified: Nov 21, 2024
CVSS 3.x
7.5
HIGH
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS 2.x
5 MEDIUM
AV:N/AC:L/Au:N/C:N/I:N/A:P
RedHat/V2
RedHat/V3
7.5 MODERATE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Ubuntu
LOW
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Additional information
NVDhttps://nvd.nist.gov/vuln/detail/CVE-2021-33503
CWEhttps://cwe.mitre.org/data/definitions/400.html

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.

Weakness

The product does not properly control the allocation and maintenance of a limited resource.

Affected Software

NameVendorStart VersionEnd Version
Urllib3Python1.25.4 (including)1.26.5 (excluding)
Red Hat Automation Hub 4.2 for RHEL 7RedHatautomation-hub-0:4.2.6-1.el7pc*
Red Hat Automation Hub 4.2 for RHEL 7RedHatpython3-chardet-0:3.0.4-3.el7pc*
Red Hat Automation Hub 4.2 for RHEL 7RedHatpython3-click-0:7.1.2-3.el7pc*
Red Hat Automation Hub 4.2 for RHEL 7RedHatpython3-gnupg-0:0.4.6-3.el7pc*
Red Hat Automation Hub 4.2 for RHEL 7RedHatpython3-jinja2-0:2.11.2-3.el7pc*
Red Hat Automation Hub 4.2 for RHEL 7RedHatpython3-markupsafe-0:1.1.1-4.el7pc*
Red Hat Automation Hub 4.2 for RHEL 7RedHatpython3-semantic-version-0:2.8.5-3.el7pc*
Red Hat Automation Hub 4.2 for RHEL 7RedHatpython-galaxy-ng-0:4.2.6-1.el7pc*
Red Hat Automation Hub 4.2 for RHEL 7RedHatpython-urllib3-0:1.26.5-1.el7pc*
Red Hat Automation Hub 4.2 for RHEL 8RedHatautomation-hub-0:4.2.6-1.el8pc*
Red Hat Automation Hub 4.2 for RHEL 8RedHatpython3-click-0:7.1.2-3.el8pc*
Red Hat Automation Hub 4.2 for RHEL 8RedHatpython3-gnupg-0:0.4.6-3.el8pc*
Red Hat Automation Hub 4.2 for RHEL 8RedHatpython3-jinja2-0:2.11.2-3.el8pc*
Red Hat Automation Hub 4.2 for RHEL 8RedHatpython3-markupsafe-0:1.1.1-4.el8pc*
Red Hat Automation Hub 4.2 for RHEL 8RedHatpython3-semantic-version-0:2.8.5-3.el8pc*
Red Hat Automation Hub 4.2 for RHEL 8RedHatpython-galaxy-ng-0:4.2.6-1.el8pc*
Red Hat Automation Hub 4.2 for RHEL 8RedHatpython-urllib3-0:1.26.5-1.el8pc*
Red Hat Enterprise Linux 8RedHatpython39:3.9-8050020210811100211.d428a79b*
Red Hat Enterprise Linux 8RedHatpython39-devel:3.9-8050020210811100211.d428a79b*
Red Hat Enterprise Linux 8RedHatpython38:3.8-8050020210811101222.e3d35cca*
Red Hat Enterprise Linux 8RedHatpython38-devel:3.8-8050020210811101222.e3d35cca*
Red Hat Satellite 6.10 for RHEL 7RedHatpython-urllib3-0:1.26.5-1.el7pc*
Red Hat Satellite 6.10 for RHEL 7RedHatpython-urllib3-0:1.26.5-1.el7pc*
Red Hat Software Collections for Red Hat Enterprise Linux 7RedHatrh-python38-babel-0:2.7.0-12.el7*
Red Hat Software Collections for Red Hat Enterprise Linux 7RedHatrh-python38-python-0:3.8.11-2.el7*
Red Hat Software Collections for Red Hat Enterprise Linux 7RedHatrh-python38-python-cryptography-0:2.8-5.el7*
Red Hat Software Collections for Red Hat Enterprise Linux 7RedHatrh-python38-python-jinja2-0:2.10.3-6.el7*
Red Hat Software Collections for Red Hat Enterprise Linux 7RedHatrh-python38-python-lxml-0:4.4.1-7.el7*
Red Hat Software Collections for Red Hat Enterprise Linux 7RedHatrh-python38-python-pip-0:19.3.1-2.el7*
Red Hat Software Collections for Red Hat Enterprise Linux 7RedHatrh-python38-python-urllib3-0:1.25.7-7.el7*
Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUSRedHatrh-python38-babel-0:2.7.0-12.el7*
Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUSRedHatrh-python38-python-0:3.8.11-2.el7*
Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUSRedHatrh-python38-python-cryptography-0:2.8-5.el7*
Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUSRedHatrh-python38-python-jinja2-0:2.10.3-6.el7*
Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUSRedHatrh-python38-python-lxml-0:4.4.1-7.el7*
Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUSRedHatrh-python38-python-pip-0:19.3.1-2.el7*
Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUSRedHatrh-python38-python-urllib3-0:1.25.7-7.el7*
Python-pipUbuntuesm-apps/focal*
Python-pipUbuntufocal*
Python-pipUbuntugroovy*
Python-pipUbuntuhirsute*
Python-pipUbuntutrusty*
Python-pipUbuntuupstream*
Python-urllib3Ubuntuesm-infra/focal*
Python-urllib3Ubuntufocal*
Python-urllib3Ubuntugroovy*
Python-urllib3Ubuntuhirsute*
Python-urllib3Ubuntutrusty*
Python-urllib3Ubuntuupstream*

Potential Mitigations

  • Mitigation of resource exhaustion attacks requires that the target system either:

  • The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question.

  • The second solution is simply difficult to effectively institute – and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.

References

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