matrix-appservice-bridge prior 8.1.2/9.0.1 improper authentication

CVSS Meta Temp Score
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CTI Interest Score
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5.2$0-$5k0.00

Summaryinfo

A vulnerability was found in matrix-appservice-bridge. It has been classified as critical. This impacts an unknown function. Performing a manipulation results in improper authentication. This vulnerability is reported as CVE-2023-38691. The attack is possible to be carried out remotely. No exploit exists. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in matrix-appservice-bridge. It has been classified as critical. This affects an unknown code block. 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. The summary by CVE is:

matrix-appservice-bridge provides an API for setting up bridges. Starting in version 4.0.0 and prior to versions 8.1.2 and 9.0.1, a malicious Matrix server can use a foreign user's MXID in an OpenID exchange, allowing a bad actor to impersonate users when using the provisioning API. The library does not check that the servername part of the `sub` parameter (containing the user's *claimed* MXID) is the the same as the servername we are talking to. A malicious actor could spin up a server on any given domain, respond with a `sub` parameter according to the user they want to act as and use the resulting token to perform provisioning requests. Versions 8.1.2 and 9.0.1 contain a patch. As a workaround, disable the provisioning API.

The weakness was disclosed 08/04/2023 as GHSA-vc7j-h8xg-fv5x. The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2023-38691 since 07/24/2023. Neither technical details nor an exploit are publicly available.

Upgrading to version 8.1.2 or 9.0.1 eliminates this vulnerability. Applying the patch 4c6723a5e7beda65cdf1ae5dbb882e8beaac8552 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.

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Productinfo

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.2

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔍

CNA Base Score: 5.0
CNA Vector (GitHub, Inc.): 🔍

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: matrix-appservice-bridge 8.1.2/9.0.1
Patch: 4c6723a5e7beda65cdf1ae5dbb882e8beaac8552

Timelineinfo

07/24/2023 🔍
08/04/2023 +11 days 🔍
08/04/2023 +0 days 🔍
08/26/2023 +22 days 🔍

Sourcesinfo

Advisory: GHSA-vc7j-h8xg-fv5x
Status: Confirmed

CVE: CVE-2023-38691 (🔍)
GCVE (CVE): GCVE-0-2023-38691
GCVE (VulDB): GCVE-100-236157

Entryinfo

Created: 08/04/2023 21:28
Updated: 08/26/2023 16:32
Changes: 08/04/2023 21:28 (50), 08/26/2023 16:32 (11)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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