FreeBSD : py-pygments -- multiple DoS vulnerabilities (cdc685b5-1724-49a1-ad57-2eaab68e9cc0)

high Nessus Plugin ID 180383



The remote FreeBSD host is missing one or more security-related updates.


The version of FreeBSD installed on the remote host is prior to tested version. It is, therefore, affected by multiple vulnerabilities as referenced in the cdc685b5-1724-49a1-ad57-2eaab68e9cc0 advisory.

- 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. (CVE-2021-20270)

- In pygments 1.1+, fixed in 2.7.4, the lexers used to parse programming languages rely heavily on regular expressions. Some of the regular expressions have exponential or cubic worst-case complexity and are vulnerable to ReDoS. By crafting malicious input, an attacker can cause a denial of service.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.


Update the affected packages.

See Also

Plugin Details

Severity: High

ID: 180383

File Name: freebsd_pkg_cdc685b5172449a1ad572eaab68e9cc0.nasl

Version: 1.0

Type: local

Published: 8/31/2023

Updated: 8/31/2023

Risk Information


Risk Factor: Medium

Score: 4.4


Risk Factor: Medium

Base Score: 5

Temporal Score: 3.9

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P

CVSS Score Source: CVE-2021-27291


Risk Factor: High

Base Score: 7.5

Temporal Score: 6.7

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:freebsd:freebsd:py310-pygments, p-cpe:/a:freebsd:freebsd:py310-pygments-25, p-cpe:/a:freebsd:freebsd:py311-pygments, p-cpe:/a:freebsd:freebsd:py311-pygments-25, p-cpe:/a:freebsd:freebsd:py37-pygments, p-cpe:/a:freebsd:freebsd:py37-pygments-25, p-cpe:/a:freebsd:freebsd:py38-pygments, p-cpe:/a:freebsd:freebsd:py38-pygments-25, p-cpe:/a:freebsd:freebsd:py39-pygments, p-cpe:/a:freebsd:freebsd:py39-pygments-25, cpe:/o:freebsd:freebsd

Required KB Items: Host/local_checks_enabled, Host/FreeBSD/release, Host/FreeBSD/pkg_info

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 8/31/2023

Vulnerability Publication Date: 3/17/2021

Reference Information

CVE: CVE-2021-20270, CVE-2021-27291