bookstackapp BookStack up to 26.05.4 Social Login handleLoginCallback driver improper authentication

CVSS Meta Temp Score
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CTI Interest Score
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7.2$0-$5k0.00

Summaryinfo

A vulnerability marked as critical has been reported in bookstackapp BookStack up to 26.05.4. Affected is the function SocialAuthService::handleLoginCallback of the component Social Login. This manipulation of the argument driver causes improper authentication. The identification of this vulnerability is CVE-2026-89022. It is possible to initiate the attack remotely. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in bookstackapp BookStack up to 26.05.4. It has been declared as critical. Affected by this vulnerability is the function SocialAuthService::handleLoginCallback of the component Social Login. The manipulation of the argument driver with an unknown input leads to a improper authentication vulnerability. The CWE definition for the vulnerability is CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

BookStack before 26.05.5 contains an authentication bypass vulnerability in its social login implementation that allows unauthenticated attackers to sign in as arbitrary users by authenticating through a different social provider sharing the same driver_id namespace. Attackers can authenticate at one enabled social provider using a user ID that matches an account linked to a different social provider, bypassing credential verification entirely because the SocialAuthService::handleLoginCallback query ignores the driver column when retrieving linked account records.

It is possible to read the advisory at bookstackapp.com. This vulnerability is known as CVE-2026-89022 since 09/10/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details of the vulnerability are known, but there is no available exploit.

Upgrading to version 26.05.5 eliminates this vulnerability.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

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: 7.3
VulDB Meta Temp Score: 7.2

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
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 authentication
CWE: CWE-287
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: BookStack 26.05.5

Timelineinfo

09/10/2026 CVE reserved
09/15/2026 +5 days Advisory disclosed
09/15/2026 +0 days VulDB entry created
09/15/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: bookstackapp.com
Status: Confirmed

CVE: CVE-2026-89022 (🔒)
GCVE (CVE): GCVE-0-2026-89022
GCVE (VulDB): GCVE-100-404359

Entryinfo

Created: 09/15/2026 18:33
Changes: 09/15/2026 18:33 (77)
Complete: 🔍
Cache ID: 216::103

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