CVE-2026-125398CoreBunch Instatic Missing Authorization
NVD
Vulnerability Summary
Instatic before 0.0.21 contains an authorization bypass vulnerability in handleRowAuthor that allows authenticated users to skip table-level access checks by loading rows with getDataRow() instead of loadRowForAccess(). Attackers holding content.edit.any but lacking data.system.tables.read can send PATCH requests to /admin/api/cms/data/rows/:id/author to read system-table rows and reassign their authors.
CVSS v4.0 Base Metrics — Score 7.1 (HIGH)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:NAttack VectorNetwork
Attack ComplexityLow
Attack RequirementsNone
Privileges RequiredLow
User InteractionNone
Confidentiality (Vulnerable System)High
Integrity (Vulnerable System)Low
Availability (Vulnerable System)None
Confidentiality (Subsequent System)None
Integrity (Subsequent System)None
Availability (Subsequent System)None
Show CVSS v3.x metrics (score 7.1)
CVSS v3.1 Base Metrics — Score 7.1 (HIGH)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:NAttack VectorNetwork
Attack ComplexityLow
Privileges RequiredLow
User InteractionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityLow
AvailabilityNone
Affected & Patched Versions
- CoreBunch Instatic < 0.0.21
- CoreBunch Instatic 0.0.21
What to do
Plan remediation soon. No exploitation is confirmed yet, but the severity is high.
- Check whether you run CoreBunch Instatic and which version.
- Update to a patched version listed above, then confirm the new version.
Timeline
- Nov 9, 2026Published
- Nov 13, 2026Record last modified
Score, severity and exploitation changes are tracked from the day Watchtower started logging them.
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Set up CVE alertsExternal References
- Vendor Advisoryhttps://github.com/CoreBunch/Instatic/security/advisories/GHSA-m425-wmrc-4v4v
- Patchhttps://github.com/CoreBunch/Instatic/commit/ff1e51eb59c860864fa24e8c3e2716b56314f3ad
- Referencehttps://github.com/CoreBunch/Instatic/releases/tag/v0.0.21
- Referencehttps://github.com/CoreBunch/Instatic/blob/v0.0.20/server/handlers/cms/data/rows.ts#L378-L398
- Referencehttps://www.vulncheck.com/advisories/instatic-before-0.0.21-authorization-bypass-via-row-author-reassignment-endpoint
Data last checked: Nov 14, 2026 00:39 UTC