MSRC_CVE-2021-3733
Vulnerability from csaf_microsoft - Published: 2022-03-02 00:00 - Updated: 2022-06-02 00:00Summary
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.
Notes
Additional Resources
To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle
Disclaimer
The information provided in the Microsoft Knowledge Base is provided \"as is\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.
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"summary": "CVE-2021-3733 There\u0027s a flaw in urllib\u0027s 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. - VEX",
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"title": "There\u0027s a flaw in urllib\u0027s 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.",
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"summary": "CVE-2021-3733 There\u0027s a flaw in urllib\u0027s 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. - VEX",
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"title": "There\u0027s a flaw in urllib\u0027s 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."
}
]
}
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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.
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