{"apiVersion":"1.0","identifier":"CVE-2026-67204","description":"BookStack before 26.05.4 contains a broken access control vulnerability that allows authenticated API users with image-update or image-delete permissions to manipulate other users- avatars by exploiting missing content-type restrictions in the Image Gallery API endpoints. Attackers can supply a user avatar-s ID to the API controller, which loads any image type without the web controller-s gallery and drawio restrictions, and when the avatar-s uploaded_to field matches a page ID accessible to the attacker, the authorization check passes allowing the attacker to rename, replace, or delete the target user-s avatar without requiring user-management permission.","publishedAt":"2026-08-24T16:17:17","lastModifiedAt":"2026-08-24T18:17:01","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-67204","cvssScore":5.4,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L","epssProbability":0.00238,"riskScore":0.55,"affectedProduct":"BookStack","affectedVersions":"<26.05.4","vulnerabilityType":"Web app","operatingSystems":[],"links":{"self":"https://www.redsauce.net/api/cves/CVE-2026-67204","webPages":{"es":"https://www.redsauce.net/es/cves/CVE-2026-67204","en":"https://www.redsauce.net/en/cves/CVE-2026-67204","fr":"https://www.redsauce.net/fr/cves/CVE-2026-67204","pt":"https://www.redsauce.net/pt/cves/CVE-2026-67204","de":"https://www.redsauce.net/de/cves/CVE-2026-67204","sk":"https://www.redsauce.net/sk/cves/CVE-2026-67204","el":"https://www.redsauce.net/el/cves/CVE-2026-67204"},"source":"https://nvd.nist.gov/vuln/detail/CVE-2026-67204"}}