Vulnerability-Lookup

GHSA-WJ55-VQCQ-GXCP

Vulnerability from github – Published: 2022-03-11 00:02 – Updated: 2026-10-14 12:31

Details

There's a flaw in urllib's AbstractBasicAuthHandler class. An attacker who controls a malicious HTTP server that an HTTP client (such as web browser) connects to, could trigger a Regular Expression Denial of Service (ReDOS) during an authentication request with a specially crafted payload that is sent by the server to the client. The greatest threat that this flaw poses is to application availability.

Severity

6.5 (Medium)


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

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  "id": "GHSA-wj55-vqcq-gxcp",
  "modified": "2026-10-14T12:31:23Z",
  "published": "2022-03-11T00:02:31Z",
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CVE-2021-3733 (GCVE-0-2021-3733)

Vulnerability from cvelistv5 – Published: 2022-03-07 00:00 – Updated: 2026-10-14 09:49

Summary

Severity

No CVSS data available.

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-10-08 20:57 UTC

CWE

CWE-400 - - Uncontrolled Resource Consumption

Assigner

redhat CNA under the redhat root

CNA scorecard B 81/100 over 1002 records in the last 180 days details

References

10 references

URL	Tags
https://bugs.python.org/issue43075
https://bugzilla.redhat.com/show_bug.cgi?id=1995234
https://github.com/python/cpython/pull/24391
https://ubuntu.com/security/CVE-2021-3733
https://github.com/python/cpython/commit/7215d1ae…
https://security.netapp.com/advisory/ntap-2022040…
https://lists.debian.org/debian-lts-announce/2023…	mailing-list
https://lists.debian.org/debian-lts-announce/2023…	mailing-list
https://lists.debian.org/debian-lts-announce/2024…
https://cert-portal.siemens.com/productcert/html/…

Impacted products

4 products

Vendor	Product	Version
n/a	python	Affected: Fixed in python v3.6.14, python v3.7.11, python v3.8.10, python v3.9.5.
Siemens	SIMATIC S7-1500 CPU 1518-4 PN/DP MFP	Affected: V3.1.0 , < V3.1.5 (custom)
Siemens	SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP	Affected: V3.1.0 , < V3.1.5 (custom)
Siemens	SIPLUS S7-1500 CPU 1518-4 PN/DP MFP	Affected: V3.1.0 , < V3.1.5 (custom)

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

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.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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