XenForo up to 2.3.12 improper authorization

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.7$0-$5k0.82+

Summaryinfo

A vulnerability categorized as critical has been discovered in XenForo up to 2.3.12. This vulnerability affects unknown code. Executing a manipulation can lead to improper authorization. This vulnerability is registered as CVE-2026-73311. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability has been found in XenForo up to 2.3.12 and classified as critical. This vulnerability affects an unknown functionality. 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, integrity, and availability. CVE summarizes:

XenForo before 2.3.13 contains an OAuth2 authorization code reuse vulnerability that allows attackers to obtain unauthorized token pairs by submitting a previously used authorization code. Attackers can exploit the failure to invalidate or mark authorization codes as consumed after initial token issuance to receive an independent token pair for the same user and scopes, bypassing the single-use guarantee of the OAuth2 authorization code flow.

The advisory is shared for download at xenforo.com. This vulnerability was named CVE-2026-73311 since 08/11/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1548.002.

Upgrading to version 2.3.13 eliminates this vulnerability.

Once again VulDB remains the best source for 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: 6.8
VulDB Meta Temp Score: 6.7

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.4
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
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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-2026-73311 (🔒)
GCVE (CVE): GCVE-0-2026-73311
GCVE (VulDB): GCVE-100-399820

Entryinfo

Created: 09/08/2026 15:42
Changes: 09/08/2026 15:42 (73)
Complete: 🔍
Cache ID: 216::103

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