CVE-2026-129427
Stored XSS via avatar upload chained with an authentication bypass in /Attachments leads to ATO
Stored XSS via avatar upload chained with an authentication bypass in /Attachments leads to ATO in Cervantes version v1.3-beta could allow an attacker to execute arbitrary code in another user's browser with elevated privileges
Fixes and workarounds
Fix
The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.
Source: CNA: GraybackFix
The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.
Source: CNA: GraybackAffected products and versions
| Product | Versions | Authority |
|---|---|---|
| cervantes CervantesSec |
≥ alpha 0.3; ≤ 1.3-beta (affected, custom) v.1.4.0-beta (unaffected) Other versions: unaffected |
CNA: Grayback |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 3.1 / 8.7 high |
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N | CNA: Grayback |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://www.grayback.es/advisoriesCNA: Grayback · patch
- https://www.grayback.es/en/advisoriesCNA: Grayback · patch
For agents and automation
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Endpoints and access details
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