CVE-2026-8340 (GCVE-0-2026-8340)
Vulnerability from cvelistv5 – Published: 2026-05-22 13:58 – Updated: 2026-05-22 17:26
VLAI?
Title
Concrete CMS 9.5.0 and below is vulnerable to CSRF via Backend\File::approveVersion
Summary
Concrete CMS 9.5.0 and below is vulnerable to CSRF via Backend\File::approveVersion. Victim with edit_file_contents permission is CSRF'd into publishing an attacker-chosen previously-uploaded version (downgrade to an older version of a file, or activation of a co-editor's unpublished version). The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 2.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Winston Crooker for reporting.
Severity ?
CWE
- CWE-352 - Cross-Site request forgery (CSRF)
Assigner
References
| URL | Tags | ||||
|---|---|---|---|---|---|
|
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Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Concrete CMS | Concrete CMS |
Affected:
5.0 , ≤ 9.5.0
(git)
|
Credits
Winston Crooker
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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