pysec - pysec-2023-25

PYSEC-2023-25

Vulnerability from pysec - Published: 2023-01-17 22:15 - Updated: 2023-05-04 03:49

Details

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.

Impacted products

Name	purl
mechanize	pkg:pypi/mechanize

Aliases

CVE-2021-32837

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "mechanize",
        "purl": "pkg:pypi/mechanize"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "dd05334448e9f39814bab044d2eaa5ef69b410d6"
            }
          ],
          "repo": "https://github.com/python-mechanize/mechanize",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.4.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.0.10a",
        "0.0.11a",
        "0.0.1a",
        "0.0.8a",
        "0.0.9a",
        "0.1.0a",
        "0.1.10",
        "0.1.11",
        "0.1.1a",
        "0.1.2b",
        "0.1.4b",
        "0.1.5b",
        "0.1.6b",
        "0.1.7b",
        "0.1.8",
        "0.1.9",
        "0.2.0",
        "0.2.1",
        "0.2.2",
        "0.2.3",
        "0.2.4",
        "0.2.5",
        "0.3.0",
        "0.3.1",
        "0.3.2",
        "0.3.3",
        "0.3.4",
        "0.3.5",
        "0.3.6",
        "0.3.7",
        "0.4.0",
        "0.4.1",
        "0.4.2",
        "0.4.3",
        "0.4.4",
        "0.4.5"
      ]
    }
  ],
  "aliases": [
    "CVE-2021-32837"
  ],
  "details": "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.",
  "id": "PYSEC-2023-25",
  "modified": "2023-05-04T03:49:46.357040Z",
  "published": "2023-01-17T22:15:00Z",
  "references": [
    {
      "type": "EVIDENCE",
      "url": "https://securitylab.github.com/advisories/GHSL-2021-108-python-mechanize-mechanize/"
    },
    {
      "type": "ADVISORY",
      "url": "https://securitylab.github.com/advisories/GHSL-2021-108-python-mechanize-mechanize/"
    },
    {
      "type": "FIX",
      "url": "https://github.com/python-mechanize/mechanize/commit/dd05334448e9f39814bab044d2eaa5ef69b410d6"
    },
    {
      "type": "EVIDENCE",
      "url": "https://github.com/python-mechanize/mechanize/blob/3acb1836f3fd8edc5a758a417dd46b53832ae3b5/mechanize/_urllib2_fork.py#L878-L879"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python-mechanize/mechanize/blob/3acb1836f3fd8edc5a758a417dd46b53832ae3b5/mechanize/_urllib2_fork.py#L878-L879"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python-mechanize/mechanize/releases/tag/v0.4.6"
    }
  ]
}

CVE-2021-32837 (GCVE-0-2021-32837)

Vulnerability from cvelistv5 – Published: 2023-01-17 00:00 – Updated: 2025-12-22 01:32

Title

mechanize vulnerable to ReDoS

Summary

Severity ?

7.5 (High)


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

CWE

CWE-1333 - Inefficient Regular Expression Complexity

Assigner

GitHub_M

References

URL

Tags

	https://securitylab.github.com/advisories/GHSL-20…
	https://github.com/python-mechanize/mechanize/blo…
	https://github.com/python-mechanize/mechanize/rel…
	https://github.com/python-mechanize/mechanize/com…
	https://lists.debian.org/debian-lts-announce/2023…	mailing-list

Impacted products

	Vendor	Product	Version
	python-mechanize	mechanize	Affected: 0.4.6 , < 0.4.6 (custom)

Show details on NVD website

JSON

To clipboard

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        "providerMetadata": {
          "dateUpdated": "2025-12-22T01:32:19.985Z",
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            "url": "https://securitylab.github.com/advisories/GHSL-2021-108-python-mechanize-mechanize/"
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            "url": "https://github.com/python-mechanize/mechanize/blob/3acb1836f3fd8edc5a758a417dd46b53832ae3b5/mechanize/_urllib2_fork.py#L878-L879"
          },
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://github.com/python-mechanize/mechanize/releases/tag/v0.4.6"
          },
          {
            "tags": [
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            ],
            "url": "https://github.com/python-mechanize/mechanize/commit/dd05334448e9f39814bab044d2eaa5ef69b410d6"
          },
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        "metrics": [
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                "id": "CVE-2021-32837",
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                  },
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                  },
                  {
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                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-03-10T21:02:11.874134Z",
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        }
      ],
      "metrics": [
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}

Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

PYSEC-2023-25

CVE-2021-32837 (GCVE-0-2021-32837)

Tags

Sightings

Nomenclature