Predictive Vulnerability Intelligence.

Product

  • Product
  • Pricing
  • Documentation

Company

  • About
  • Partnerships
  • Blog
  • Support

Legal

  • Terms
  • Privacy
  • Data Licensing

© 2026 FAUCET Technologies LLC. All rights reserved.

CVE-2021-32837

39
FAUCET Score

CVE-2021-32837 describes a Regular Expression Denial of Service (ReDoS) vulnerability in the mechanize library, affecting versions prior to 0.4.6. A maliciously crafted web server response can trigger this flaw, causing the mechanize client to crash. With a CVSS score of 7.5 (High), this vulnerability is remotely exploitable with low attack complexity, leading to high availability impact. There is currently no evidence of active exploitation, public exploit code, or significant community discussion surrounding this CVE.

Impacted Technologies

VendorProductVersion(s)CPE
< 0.4.6CPE matchmatch criteria
cpe:2.3:a:mechanize_project:mechanize:*:*:*:*:*:python:*:*

CVSS Data

CVSS version used by this source: 3.1

7.5HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
Exploitability Score
3.9
Impact Score
3.6
CvssVersion
3.1

Exploit Intelligence

EPSS Score
28.66%
Probability of exploitation in next 30 days
EPSS Percentile
97.9%
Percentile rank of EPSS score among Peer Group
As of 2026-07-27
Model: v2026.06.15
This CVE's current EPSS score of 0.2866 is in the 97th percentile among its peer group of 51,551 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.1 Mastodon, and 0.4 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (2)

github_advisorypatch availablevia nvd_reference
View patch
pippatch availablevia ghsa
Product: mechanizeFixed in: 0.4.6

Vendor Advisories (1)

pipGHSA-g3pv-pj5f-3hfqhigh

mechanize Regular Expression Denial of Service vulnerability

Jan 18, 2023

References

lists.debian.org / debian-lts-announce/2025/12/msg00028.html
github.com / python-mechanize/mechanize/blob/3acb1836f3fd8edc5a758a417dd46b53832ae3b5/mechanize/_urllib2_fork.py
ExploitThird Party Advisory
github.com / python-mechanize/mechanize/commit/dd05334448e9f39814bab044d2eaa5ef69b410d6
PatchThird Party Advisory
github.com / python-mechanize/mechanize/releases/tag/v0.4.6
Third Party Advisory
lists.debian.org / debian-lts-announce/2023/06/msg00022.html
securitylab.github.com / advisories/GHSL-2021-108-python-mechanize-mechanize
ExploitThird Party Advisory