How severe is CVE-2021-32837?

CVE-2021-32837 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-32837 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 29% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-32837?

CVE-2021-32837 affects Mechanize Project Mechanize. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-32837?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-32837 published?

CVE-2021-32837 was published on 2023-01-17 and last updated on 2026-06-17.

CVE-2021-32837

CVE-2021-32837 is a high-severity vulnerability in Mechanize Project Mechanize with a CVSS 3.x base score of 7.5. Its EPSS exploit-prediction score of 29% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-1333.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 29% (98th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1333
Affected product: Mechanize Project Mechanize
Published: 2023-01-17
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2021-32837?: 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.
How severe is CVE-2021-32837?: CVE-2021-32837 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-32837 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 29% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-32837?: CVE-2021-32837 affects Mechanize Project Mechanize. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-32837?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-32837 published?: CVE-2021-32837 was published on 2023-01-17 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:mechanize_project:mechanize:*:*:*:*:*:python:*:*

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