CVE-2026-121458

HIGH
MEDIUM Priority: 0.02 BB Relevance: 64/100
Published: 2026-11-03 Modified: 2026-11-03 First seen: 2026-11-03 Status: active

Attack Surface

Network Low Complexity No Interaction Conf. Impact

CVSS Vector Breakdown

AV: Network
AC: Low
PR: Low
UI: None
S: X
AT: None
VC: High
VI: None
VA: None

Description

Instatic before 0.0.21 contains a missing authorization vulnerability in its AI/MCP content read tools that allows low-privileged authenticated users with ai.chat and content.edit.own capabilities to access data rows belonging to other users by calling content_get_document and content_list_documents without the object-level authorization checks enforced by the normal HTTP API. Attackers can use the MCP interface to retrieve private or unpublished draft content and enumerate rows from the posts system table, resulting in cross-user data disclosure.

Weakness Classification (1)

Affected Software (2)

VendorProductVersion
CoreBunch Instatic 0.0.12 < 0.0.21
CoreBunch Instatic 0.0.12 < 0.0.21

Bug Bounty Relevance

64 / 100
✓ Network accessible
✓ Low complexity
✓ No user interaction

CVSS Score

7.1 / 10.0 v4.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS — Exploitation Probability

0.31%
Raw Score 0.003090
Percentile 23.9%
Date 2026-11-07

EPSS Trend

2026-11-07
0.00309
2026-11-06
0.00309
2026-11-05
0.00309
2026-11-04
0.00309

Intelligence Sources

mitre ref →
nvd ref →