CVE-2026-86347
MISP Missing Authorization on Template File Upload Allows Authenticated Disk Exhaustion
Description
Affected versions of MISP allow any authenticated user to access TemplatesController::uploadFile() because the ACL entry for templates/uploadFile used the wildcard *. This bypasses the intended role restrictions applied to neighboring template-management operations. The upload handler accepts arbitrary content with only minimal checks and writes it into app/tmp/files/. A low-privileged or read-only user can therefore repeatedly upload files and consume server disk space without requiring perm_add or perm_template. The fix changes the ACL requirement from * to perm_add. The commit also rules out stronger impacts: uploaded files receive random names, path traversal/predictable overwrite is not available, the temporary directory is outside the web root, and the files are not directly served over HTTP. Therefore, the issue should not be described as arbitrary file overwrite, stored XSS, or RCE. Version affected: ≤2.5.45
INFO
Published Date :
Sept. 7, 2026, 10:16 a.m.
Last Modified :
Sept. 7, 2026, 10:16 a.m.
Remotely Exploit :
Yes !
Source :
5a6e4751-2f3f-4070-9419-94fb35b644e8
Affected Products
The following products are affected by CVE-2026-86347
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | HIGH | 5a6e4751-2f3f-4070-9419-94fb35b644e8 | ||||
| CVSS 4.0 | HIGH | 5a6e4751-2f3f-4070-9419-94fb35b644e8 |
Solution
- Update MISP to version 2.5.46 or later.
- Apply the access control change to templates/uploadFile.
- Ensure ACL entry for templates/uploadFile requires 'perm_add'.
- Verify role restrictions for template management.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-86347.
| URL | Resource |
|---|---|
| https://github.com/MISP/MISP/commit/8e8885971 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-86347 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-86347
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-86347 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-86347 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by 5a6e4751-2f3f-4070-9419-94fb35b644e8
Sep. 07, 2026
Action Type Old Value New Value Added Description Affected versions of MISP allow any authenticated user to access TemplatesController::uploadFile() because the ACL entry for templates/uploadFile used the wildcard *. This bypasses the intended role restrictions applied to neighboring template-management operations. The upload handler accepts arbitrary content with only minimal checks and writes it into app/tmp/files/. A low-privileged or read-only user can therefore repeatedly upload files and consume server disk space without requiring perm_add or perm_template. The fix changes the ACL requirement from * to perm_add. The commit also rules out stronger impacts: uploaded files receive random names, path traversal/predictable overwrite is not available, the temporary directory is outside the web root, and the files are not directly served over HTTP. Therefore, the issue should not be described as arbitrary file overwrite, stored XSS, or RCE. Version affected: ≤2.5.45 Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/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 Added CWE CWE-400 Added CWE CWE-862 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/86xxx/CVE-2026-86347.json">CVE-2026-86347</a> Added Reference https://github.com/MISP/MISP/commit/8e8885971