Vulnerabilities
Misconfiguration
Compliance
CVE Vulnerabilities

CVE-2021-20270

Loop with Unreachable Exit Condition ('Infinite Loop')

Published: Mar 23, 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
MEDIUM
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Additional information
NVDhttps://nvd.nist.gov/vuln/detail/CVE-2021-20270
CWEhttps://cwe.mitre.org/data/definitions/835.html

An infinite loop in SMLLexer in Pygments versions 1.5 to 2.7.3 may lead to denial of service when performing syntax highlighting of a Standard ML (SML) source file, as demonstrated by input that only contains the exception keyword.

Weakness

The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop.

Affected Software

NameVendorStart VersionEnd Version
PygmentsPygments1.5 (including)2.7.3 (including)
Red Hat Automation Hub 4.2 for RHEL 7RedHatautomation-hub-0:4.2.2-1.el7pc*
Red Hat Automation Hub 4.2 for RHEL 7RedHatpython3-django-0:2.2.18-1.el7pc*
Red Hat Automation Hub 4.2 for RHEL 7RedHatpython-bleach-0:3.3.0-1.el7pc*
Red Hat Automation Hub 4.2 for RHEL 7RedHatpython-bleach-allowlist-0:1.0.3-1.el7pc*
Red Hat Automation Hub 4.2 for RHEL 7RedHatpython-galaxy-importer-0:0.2.15-1.el7pc*
Red Hat Automation Hub 4.2 for RHEL 7RedHatpython-galaxy-ng-0:4.2.2-1.el7pc*
Red Hat Automation Hub 4.2 for RHEL 7RedHatpython-pulp-ansible-1:0.5.6-1.el7pc*
Red Hat Automation Hub 4.2 for RHEL 8RedHatautomation-hub-0:4.2.2-1.el8pc*
Red Hat Automation Hub 4.2 for RHEL 8RedHatpython3-django-0:2.2.18-1.el8pc*
Red Hat Automation Hub 4.2 for RHEL 8RedHatpython-bleach-0:3.3.0-1.el8pc*
Red Hat Automation Hub 4.2 for RHEL 8RedHatpython-bleach-allowlist-0:1.0.3-1.el8pc*
Red Hat Automation Hub 4.2 for RHEL 8RedHatpython-galaxy-importer-0:0.2.15-1.el8pc*
Red Hat Automation Hub 4.2 for RHEL 8RedHatpython-galaxy-ng-0:4.2.2-1.el8pc*
Red Hat Automation Hub 4.2 for RHEL 8RedHatpython-pulp-ansible-1:0.5.6-1.el8pc*
Red Hat Enterprise Linux 8RedHatpython36:3.6-8050020210811103506.982725ab*
Red Hat Enterprise Linux 8RedHatpython27:2.7-8050020210811095446.3e7ace8b*
Red Hat Enterprise Linux 8RedHatresource-agents-0:4.1.1-98.el8*
Red Hat Software Collections for Red Hat Enterprise Linux 7RedHatpython27-babel-0:0.9.6-10.el7*
Red Hat Software Collections for Red Hat Enterprise Linux 7RedHatpython27-python-0:2.7.18-3.el7*
Red Hat Software Collections for Red Hat Enterprise Linux 7RedHatpython27-python-jinja2-0:2.6-16.el7*
Red Hat Software Collections for Red Hat Enterprise Linux 7RedHatpython27-python-pygments-0:1.5-5.el7*
Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUSRedHatpython27-babel-0:0.9.6-10.el7*
Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUSRedHatpython27-python-0:2.7.18-3.el7*
Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUSRedHatpython27-python-jinja2-0:2.6-16.el7*
Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUSRedHatpython27-python-pygments-0:1.5-5.el7*
PygmentsUbuntubionic*
PygmentsUbuntudevel*
PygmentsUbuntuesm-infra-legacy/trusty*
PygmentsUbuntuesm-infra/bionic*
PygmentsUbuntuesm-infra/focal*
PygmentsUbuntuesm-infra/xenial*
PygmentsUbuntufocal*
PygmentsUbuntugroovy*
PygmentsUbuntuhirsute*
PygmentsUbuntuimpish*
PygmentsUbuntujammy*
PygmentsUbuntukinetic*
PygmentsUbuntulunar*
PygmentsUbuntuprecise/esm*
PygmentsUbuntutrusty*
PygmentsUbuntutrusty/esm*
PygmentsUbuntuupstream*
PygmentsUbuntuxenial*

References

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