miguelgrinberg Flask-HTTPAuth up to 4.8.0 on Flask improper authentication

CVSS Meta Temp Score
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CTI Interest Score
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6.7$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in miguelgrinberg Flask-HTTPAuth up to 4.8.0 on Flask. The impacted element is an unknown function. Performing a manipulation results in improper authentication. This vulnerability is identified as CVE-2026-34531. The attack can be initiated remotely. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in miguelgrinberg Flask-HTTPAuth up to 4.8.0 on Flask. This affects some unknown processing. The manipulation with an unknown input leads to a improper authentication vulnerability. CWE is classifying the issue as CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Flask-HTTPAuth provides Basic, Digest and Token HTTP authentication for Flask routes. Prior to version 4.8.1, in a situation where the client makes a request to a token protected resource without passing a token, or passing an empty token, Flask-HTTPAuth would invoke the application's token verification callback function with the token argument set to an empty string. If the application had any users in its database with an empty string set as their token, then it could potentially authenticate the client request against any of those users. This issue has been patched in version 4.8.1.

The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-34531 since 03/30/2026. The exploitability is told to be difficult. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available.

Upgrading to version 4.8.1 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch b15ffe9e50e110d7174ccd944f642079e1dcf9ee is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at CNNVD (CNNVD-202604-218). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

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Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.8
VulDB Meta Temp Score: 6.7

VulDB Base Score: 5.6
VulDB Temp Score: 5.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 8.2
NVD Vector: 🔒

CNA Base Score: 6.5
CNA Vector (GitHub_M): 🔒

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Improper authentication
CWE: CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Flask-HTTPAuth 4.8.1
Patch: b15ffe9e50e110d7174ccd944f642079e1dcf9ee

Timelineinfo

03/30/2026 CVE reserved
04/02/2026 +3 days Advisory disclosed
04/02/2026 +0 days VulDB entry created
06/01/2026 +60 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-p44q-vqpr-4xmg
Status: Confirmed

CVE: CVE-2026-34531 (🔒)
GCVE (CVE): GCVE-0-2026-34531
GCVE (VulDB): GCVE-100-354801
CNNVD: CNNVD-202604-218 - Flask-HTTPAuth 授权问题漏洞

Entryinfo

Created: 04/02/2026 02:42
Updated: 06/01/2026 03:37
Changes: 04/02/2026 02:42 (68), 04/02/2026 22:37 (6), 06/01/2026 03:37 (11)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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