CVE-2026-89022 (GCVE-0-2026-89022)
Vulnerability from cvelistv5 – Published: 2026-09-15 16:11 – Updated: 2026-10-01 15:21 X_Open Source
VLAI
EPSS
VEX
Title
BookStack < 26.05.5 Authentication Bypass via Social Login Provider Confusion
Summary
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.
Severity
7.4 (High)
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-15 19:04 UTC
CWE
- CWE-290 - Authentication Bypass by Spoofing
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://www.bookstackapp.com/blog/bookstack-relea… | vendor-advisory |
| https://www.vulncheck.com/advisories/bookstack-au… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| bookstackapp | bookstack |
Affected:
0 , < 26.05.5
(custom)
cpe:2.3:a:bookstackapp:bookstack:*:*:*:*:*:*:*:* |
Date Public
2026-09-14 00:00
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Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
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They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.