mechanize, a library for automatically interacting with HTTP web servers, contains a regular expression that is vulnerable to regular expression denial of service (ReDoS) prior to version 0.4.6. If a web server responds in a malicious way, then mechanize could crash. Version 0.4.6 has a patch for the issue.

The remote Debian 11 host has a package installed that is affected by a vulnerability as referenced in the dla-4418 advisory.

    -------------------------------------------------------------------------     Debian LTS Advisory DLA-4418-1                debian-lts@lists.debian.org     https://www.debian.org/lts/security/                       Daniel Leidert     December 22, 2025                             https://wiki.debian.org/LTS
    -------------------------------------------------------------------------

    Package        : python-mechanize     Version        : 1:0.4.5-2+deb11u1     CVE ID         : CVE-2021-32837

    Erik Krogh Kristensen and Rasmus Petersen from the GitHub Security Lab     discovered a ReDoS (Regular Expression Denial of Service) vulnerability     in python-mechanize, a library to automate interaction with websites     modeled after the Perl module WWW::Mechanize, which could lead to     Denial of Service when parsing a malformed authentication header.

    For Debian 11 bullseye, this problem has been fixed in version     1:0.4.5-2+deb11u1.

    We recommend that you upgrade your python-mechanize packages.

    For the detailed security status of python-mechanize please refer to     its security tracker page at:
    https://security-tracker.debian.org/tracker/python-mechanize

    Further information about Debian LTS security advisories, how to apply     these updates to your system and frequently asked questions can be     found at: https://wiki.debian.org/LTS     Attachment:
    signature.asc     Description: This is a digitally signed message part

Tenable has extracted the preceding description block directly from the Debian security advisory.

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

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - mechanize, a library for automatically interacting with HTTP web servers, contains a regular expression     that is vulnerable to regular expression denial of service (ReDoS) prior to version 0.4.6. If a web server     responds in a malicious way, then mechanize could crash. Version 0.4.6 has a patch for the issue.
    (CVE-2021-32837)

Note that Nessus relies on the presence of the package as reported by the vendor.

The remote Debian 10 host has packages installed that are affected by a vulnerability as referenced in the dla-3460 advisory.

    -------------------------------------------------------------------------     Debian LTS Advisory DLA-3460-1                debian-lts@lists.debian.org     https://www.debian.org/lts/security/                       Guilhem Moulin     June 20, 2023                                 https://wiki.debian.org/LTS
    -------------------------------------------------------------------------

    Package        : python-mechanize     Version        : 1:0.2.5-3+deb10u1     CVE ID         : CVE-2021-32837

    Erik Krogh Kristensen and Rasmus Petersen from the GitHub Security Lab     discovered a ReDoS (Regular Expression Denial of Service) vulnerability     in python-mechanize, a library to automate interaction with websites     modeled after the Perl module WWW::Mechanize, which could lead to     Denial of Service when parsing a malformed authentication header.

    For Debian 10 buster, this problem has been fixed in version     1:0.2.5-3+deb10u1.

    We recommend that you upgrade your python-mechanize packages.

    For the detailed security status of python-mechanize please refer to     its security tracker page at:
    https://security-tracker.debian.org/tracker/python-mechanize

    Further information about Debian LTS security advisories, how to apply     these updates to your system and frequently asked questions can be     found at: https://wiki.debian.org/LTS     Attachment:
    signature.asc     Description: PGP signature

Tenable has extracted the preceding description block directly from the Debian security advisory.

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

The remote openSUSE 15 host has a package installed that is affected by a vulnerability as referenced in the openSUSE- SU-2023:0030-1 advisory.

  - mechanize, a library for automatically interacting with HTTP web servers, contains a regular expression     that is vulnerable to regular expression denial of service (ReDoS) prior to version 0.4.6. If a web server     responds in a malicious way, then mechanize could crash. Version 0.4.6 has a patch for the issue.
    (CVE-2021-32837)

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

ID	Name	Product	Family	Severity
279499	Debian dla-4418 : python3-mechanize - security update	Nessus	Debian Local Security Checks	high
223931	Linux Distros Unpatched Vulnerability : CVE-2021-32837	Nessus	Misc.	high
177456	Debian dla-3460 : python-clientform - security update	Nessus	Debian Local Security Checks	high
170494	openSUSE 15 Security Update : python-mechanize (openSUSE-SU-2023:0030-1)	Nessus	SuSE Local Security Checks	high

Detections

Analytics

CVE-2021-32837

high

Tenable Plugins

high

high

high

high