High severity · published May 20, 2026
CVE-2026-9137
CSP Report Endpoint Log Flooding in MISP via Incorrect Size Limit
7.5
CVSS
0.4%
EPSS
No
On KEV
Description
The CSP report endpoint in MISP intended to limit logged CSP reports to 1 KB but incorrectly allowed reports up to 1 MB before truncation. On deployments where the endpoint is reachable by untrusted clients, this could allow attackers to generate excessive log volume and contribute to resource exhaustion or log flooding.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 30% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MI
misp · misp
2.5.0 through 2.5.37 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-9137
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-9137
Patch
https://github.com/MISP/MISP/commit/02932cccab230b295afcaf5aa05e363d30db0ec9
More from misp
10.0
CVE-2026-10611
OTP bypass via plugin-based LDAP authentication in MISP when LDAP mixed authentication is enabled
9.8
CVE-2026-85216
MISP LDAP and LinOTP Authentication Bypass via Empty or Invalid Credentials
9.8
CVE-2024-29858
In MISP before 2.4.187, __uploadLogo in app/Controller/OrganisationsController.php does not properly check for a valid logo upload
9.8
CVE-2024-29859
In MISP before 2.4.187, add_misp_export in app/Controller/EventsController.php does not properly check for a valid file upload
9.8
CVE-2024-25674
An issue was discovered in MISP before 2.4.184