Vulnerability-Lookup

GHSA-WJ55-VQCQ-GXCP

Vulnerability from github – Published: 2022-03-11 00:02 – Updated: 2025-11-04 00:30

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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  "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: 2025-11-03 21:45

Summary

Severity

No CVSS data available.

CWE

CWE-400 - - Uncontrolled Resource Consumption

Assigner

redhat redhat root

References

9 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…

Impacted products

1 product

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.

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JSON

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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.

Detection rules are retrieved from Rulezet.

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.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.