XenForo up to 2.3.12 OAuth2 Token Endpoint improper authorization

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.0$0-$5k1.23+

Summaryinfo

A vulnerability was found in XenForo up to 2.3.12. It has been classified as problematic. Affected by this vulnerability is an unknown functionality of the component OAuth2 Token Endpoint. This manipulation causes improper authorization. This vulnerability is tracked as CVE-2026-73310. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability classified as problematic was found in XenForo up to 2.3.12. Affected by this vulnerability is an unknown code block of the component OAuth2 Token Endpoint. The manipulation with an unknown input leads to a improper authorization vulnerability. The CWE definition for the vulnerability is CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. As an impact it is known to affect confidentiality. The summary by CVE is:

XenForo before 2.3.13 contains an authorization flaw in the OAuth2 token endpoint that allows attackers controlling any allowlisted redirect URI to bypass redirect URI binding by submitting a different allowlisted URI than the one recorded at authorization time. Attackers can exchange an intercepted authorization code using a mismatched redirect URI to steal OAuth2 tokens from intercepted authorization flows.

The advisory is shared at xenforo.com. This vulnerability is known as CVE-2026-73310 since 08/11/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1548.002 for this issue.

Upgrading to version 2.3.13 eliminates this vulnerability.

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

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.1
VulDB Meta Temp Score: 5.0

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

CNA Base Score: 5.9
CNA Vector (VulnCheck): 🔒

CVSSv2info

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

Exploitinginfo

Class: Improper authorization
CWE: CWE-285 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
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: XenForo 2.3.13

Timelineinfo

08/11/2026 CVE reserved
09/08/2026 +28 days Advisory disclosed
09/08/2026 +0 days VulDB entry created
09/08/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: xenforo.com
Status: Confirmed

CVE: CVE-2026-73310 (🔒)
GCVE (CVE): GCVE-0-2026-73310
GCVE (VulDB): GCVE-100-399817

Entryinfo

Created: 09/08/2026 15:40
Changes: 09/08/2026 15:40 (74)
Complete: 🔍
Cache ID: 216::103

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

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