High severity · published Mar 23, 2021
CVE-2021-20270
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…
7.5
CVSS
2.8%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.8% · higher than 86% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
9.0; 10.0 · source: NVD
EL
Enterprise Linux · Redhat
7.0; 8.0 · source: NVD
FE
Fedora · Fedoraproject
33 · source: NVD
OC
Openshift Container Platform · Redhat
3.11; 4.0 · source: NVD
OP
Openstack Platform · Redhat
10.0 · source: NVD
PY
Pygments · Pygments
1.5 through 2.7.3 · source: NVD
SC
Software Collections · Redhat
All versions, or not specified · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-20270
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-20270
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=1922136
Mailing List
https://lists.debian.org/debian-lts-announce/2021/05/msg00003.html
Mailing List
https://lists.debian.org/debian-lts-announce/2021/05/msg00006.html
Third Party Advisory
https://www.debian.org/security/2021/dsa-4889
Not Applicable
https://www.oracle.com/security-alerts/cpuoct2021.html
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