7.5
CWE
835
Advisory Published
CVE Published
Advisory Published
Updated

CVE-2021-20270

First published: Thu Dec 10 2020(Updated: )

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.

Credit: secalert@redhat.com secalert@redhat.com

Affected SoftwareAffected VersionHow to fix
ubuntu/pygments<2.7.1+dfsg-2
2.7.1+dfsg-2
ubuntu/pygments<1.6+dfsg-1ubuntu1.1+
1.6+dfsg-1ubuntu1.1+
ubuntu/pygments<2.2.0+dfsg-1ubuntu0.1
2.2.0+dfsg-1ubuntu0.1
ubuntu/pygments<2.3.1+dfsg-1ubuntu2.1
2.3.1+dfsg-1ubuntu2.1
ubuntu/pygments<2.3.1+dfsg-4ubuntu0.1
2.3.1+dfsg-4ubuntu0.1
ubuntu/pygments<2.7.1+dfsg-2
2.7.1+dfsg-2
ubuntu/pygments<2.7.4
2.7.4
ubuntu/pygments<2.1+dfsg-1ubuntu0.1
2.1+dfsg-1ubuntu0.1
ubuntu/pygments<2.7.1+dfsg-2
2.7.1+dfsg-2
ubuntu/pygments<2.7.1+dfsg-2
2.7.1+dfsg-2
ubuntu/pygments<2.7.1+dfsg-2
2.7.1+dfsg-2
redhat/automation-hub<0:4.2.2-1.el7
0:4.2.2-1.el7
redhat/python3-django<0:2.2.18-1.el7
0:2.2.18-1.el7
redhat/python-bleach<0:3.3.0-1.el7
0:3.3.0-1.el7
redhat/python-bleach-allowlist<0:1.0.3-1.el7
0:1.0.3-1.el7
redhat/python-galaxy-importer<0:0.2.15-1.el7
0:0.2.15-1.el7
redhat/python-galaxy-ng<0:4.2.2-1.el7
0:4.2.2-1.el7
redhat/python-pulp-ansible<1:0.5.6-1.el7
1:0.5.6-1.el7
redhat/automation-hub<0:4.2.2-1.el8
0:4.2.2-1.el8
redhat/python3-django<0:2.2.18-1.el8
0:2.2.18-1.el8
redhat/python-bleach<0:3.3.0-1.el8
0:3.3.0-1.el8
redhat/python-bleach-allowlist<0:1.0.3-1.el8
0:1.0.3-1.el8
redhat/python-galaxy-importer<0:0.2.15-1.el8
0:0.2.15-1.el8
redhat/python-galaxy-ng<0:4.2.2-1.el8
0:4.2.2-1.el8
redhat/python-pulp-ansible<1:0.5.6-1.el8
1:0.5.6-1.el8
redhat/resource-agents<0:4.1.1-98.el8
0:4.1.1-98.el8
redhat/python27-babel<0:0.9.6-10.el7
0:0.9.6-10.el7
redhat/python27-python<0:2.7.18-3.el7
0:2.7.18-3.el7
redhat/python27-python-jinja2<0:2.6-16.el7
0:2.6-16.el7
redhat/python27-python-pygments<0:1.5-5.el7
0:1.5-5.el7
debian/mediawiki
1:1.31.16-1+deb10u2
1:1.31.16-1+deb10u6
1:1.35.11-1~deb11u1
1:1.35.13-1~deb11u1
1:1.39.4-1~deb12u1
1:1.39.5-1~deb12u1
1:1.39.5-1
debian/pygments
2.3.1+dfsg-1+deb10u2
2.7.1+dfsg-2.1
2.14.0+dfsg-1
2.15.1+dfsg-1
redhat/python-pygments<2.7.4
2.7.4
pip/Pygments>=1.5<2.7.4
2.7.4
Pygments Pygments>=1.5<=2.7.3
Red Hat OpenShift Container Platform=3.11
Red Hat OpenShift Container Platform=4.0
Red Hat OpenStack Platform=10.0
Redhat Software Collections
Red Hat Enterprise Linux=7.0
Red Hat Enterprise Linux=8.0
Fedoraproject Fedora=33
Debian Debian Linux=9.0
Debian Debian Linux=10.0

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Frequently Asked Questions

  • What is the vulnerability ID for this issue?

    The vulnerability ID for this issue is CVE-2021-20270.

  • What is the severity level of CVE-2021-20270?

    The severity level of CVE-2021-20270 is high, with a CVSS score of 7.5.

  • Which software versions are affected by CVE-2021-20270?

    Pygments versions 1.5 to 2.7.3 are affected by CVE-2021-20270.

  • How can I fix the vulnerability in Pygments?

    To fix the vulnerability, update Pygments to version 2.7.4.

  • Where can I find more information about CVE-2021-20270?

    More information about CVE-2021-20270 can be found at the following references: [Reference 1](https://bugzilla.redhat.com/show_bug.cgi?id=1922136), [Reference 2](https://www.debian.org/security/2021/dsa-4889), [Reference 3](https://lists.debian.org/debian-lts-announce/2021/05/msg00003.html).

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