FreeBSD : py-bleach -- regular expression denial-of-service (4c52ec3c-86f3-11ea-b5b4-641c67a117d8)

high Nessus Plugin ID 136003


New! Plugin Severity Now Using CVSS v3

The calculated severity for Plugins has been updated to use CVSS v3 by default. Plugins that do not have a CVSS v3 score will fall back to CVSS v2 for calculating severity. Severity display preferences can be toggled in the settings dropdown.


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


Bleach developers reports :

bleach.clean behavior parsing style attributes could result in a regular expression denial of service (ReDoS).

Calls to bleach.clean with an allowed tag with an allowed style attribute are vulnerable to ReDoS. For example, bleach.clean(..., attributes={'a': ['style']}).


Update the affected packages.

See Also

Plugin Details

Severity: High

ID: 136003

File Name: freebsd_pkg_4c52ec3c86f311eab5b4641c67a117d8.nasl

Version: 1.2

Type: local

Published: 4/27/2020

Updated: 4/20/2021

Dependencies: ssh_get_info.nasl

Risk Information

CVSS Score Source: CVE-2020-6817


Risk Factor: Medium

Score: 4.4


Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

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

Temporal Vector: E:U/RL:OF/RC:C


Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

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

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:freebsd:freebsd:py27-bleach, p-cpe:/a:freebsd:freebsd:py35-bleach, p-cpe:/a:freebsd:freebsd:py36-bleach, p-cpe:/a:freebsd:freebsd:py37-bleach, p-cpe:/a:freebsd:freebsd:py38-bleach, cpe:/o:freebsd:freebsd

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

Exploit Ease: No known exploits are available

Patch Publication Date: 4/26/2020

Vulnerability Publication Date: 3/9/2019

Reference Information

CVE: CVE-2020-6817